I. Finland before the Crusades
In the twelfth century the land that is now Finland was inhabited by several Finnic peoples. The Finns proper lived in the southwest, around the later city of Turku. The Tavastians, or Häme, lived in the interior lakeland. The Karelians lived to the east, around Lake Ladoga, and the Sámi lived in the north. They lived by farming, hunting, fishing and trade, especially in furs, and they had hill forts and trading places but no towns or central government.
The Finns had long contacts with the Scandinavians across the Gulf of Bothnia and with the Russians of Novgorod to the east. Some Christian influence had already reached Finland from both directions, as shown by graves without grave goods, crosses and other finds from the eleventh and twelfth centuries in southwestern Finland. The Karelians were drawn into the orbit of Novgorod and Orthodox Christianity. The site's page on the Northern Crusades describes the broader context of the Baltic crusades.
II. The Swedes
Sweden in the twelfth century was a kingdom in formation, divided between rival dynasties, the house of Sverker and the house of Eric, which fought for the throne. Christianity had been established in Sweden in the eleventh century, and in 1164 the archbishopric of Uppsala was founded. The Swedes had trading interests in the eastern Baltic, and Swedish and Gotlandic merchants travelled through the Gulf of Finland to Novgorod.
The Finns and Karelians raided the Swedish coasts, and in 1187 a raid, perhaps by Karelians or Estonians, sacked the Swedish trading town of Sigtuna and killed the archbishop of Uppsala, Johannes. The raids gave the Swedes a motive for war, and the crusading idea gave them a justification.
III. Eric IX and Bishop Henry
According to the legend of St Eric, written in the late thirteenth century, King Eric IX of Sweden, who ruled from about 1156 to 1160, led a crusade to Finland with Bishop Henry of Uppsala. The king offered peace and the faith to the Finns, and when they refused, he defeated them in battle and had them baptised. Eric is said to have wept over the dead, because they had died without baptism. He then returned to Sweden, leaving Henry to continue the mission.
Eric was murdered in 1160 at Uppsala by a Danish prince, Magnus Henriksen, who claimed the throne. He was venerated as a saint and became the patron saint of Sweden, though he was never formally canonised. His relics are kept in Uppsala Cathedral, and his image appears on the coat of arms of Stockholm.
The historicity of Eric's crusade is doubtful. The legend was written over a century after the events, and no contemporary source mentions the crusade. Many historians regard it as a later invention, designed to provide a founding story for the Swedish church in Finland and to justify Swedish rule. Others believe it reflects a real expedition, perhaps a smaller one than the legend describes.
IV. Henry of Uppsala
According to the legend of St Henry, Bishop Henry was an Englishman who came to Sweden with the papal legate Nicholas Breakspear, later Pope Adrian IV, the only English pope. After the crusade Henry remained in Finland to preach. He was killed on the ice of Lake Köyliö by a Finnish peasant named Lalli, whom he had rebuked for killing a man, or, in another version, because Henry had taken food from his house without payment.
According to the folk poem on the death of Henry, Lalli killed the bishop with an axe and took his mitre. When he tried to remove it from his head, his scalp came off with it, and he died a miserable death, as punishment. Henry was venerated as a martyr and became the patron saint of Finland. His relics were moved to Turku Cathedral in 1300, and the pilgrimage to the place of his death became an important part of Finnish religious life.
Like the legend of Eric, the legend of Henry is late and uncertain. Some historians doubt that Henry existed at all, while others accept that a missionary bishop was killed in Finland in the mid-twelfth century. The figure of Lalli became a symbol in Finnish national memory, sometimes as a murderer, sometimes as a defender of Finnish freedom against foreign rule.
V. Papal Letters
The earliest contemporary sources for the Christianisation of Finland are papal letters. In about 1171 Pope Alexander III wrote to the Swedish archbishop and princes complaining that the Finns promised to accept the faith whenever an enemy army threatened them, but abandoned it and persecuted the clergy as soon as the army left. He urged the Swedes to bind the Finns more firmly to the faith by keeping control of their forts.
In 1209 Innocent III wrote about a bishop in Finland, and in 1229 Gregory IX placed the Finnish converts under papal protection and allowed the bishop of Finland to move his seat to a safer place. In 1237 Gregory IX called for a crusade against the Tavastians, who had returned to paganism and attacked the church, and he granted the crusaders the same indulgence as those going to the Holy Land. The papal letters show that the Swedish church in Finland faced serious resistance in the early thirteenth century.
VI. Thomas, Bishop of Finland
The first bishop of Finland known from contemporary sources was Thomas, possibly an Englishman, who held office from about 1220 to 1245. He worked to strengthen the church in southwestern Finland, obtaining papal privileges and seeking military support. Gregory IX's call for a crusade against the Tavastians in 1237 was probably in response to his requests. In 1245 Thomas resigned after confessing to forging a papal letter and to having a man tortured, and he retired to the Dominican convent in Visby on Gotland, where he died in 1248.
Thomas's career shows the difficulties of the early Finnish church: a bishop with few resources, dependent on Swedish military help, facing pagan resistance and competition from Novgorod. The bishopric was moved from Nousiainen to Koroinen and finally to Turku, where the cathedral was consecrated in 1300.
VII. Birger Jarl in Tavastia
The second Swedish crusade, as it is traditionally called, was led by Birger Jarl, the most powerful man in Sweden in the mid-thirteenth century, who ruled for his young son, King Valdemar. According to the Chronicle of Eric, a Swedish rhymed chronicle of the early fourteenth century, Birger led an expedition to Tavastia, defeated the Tavastians and forced them to accept baptism, and built the castle of Tavastehus, now Hämeenlinna. The date of the expedition is uncertain, usually given as 1249 or 1238–1239.
The conquest of Tavastia brought central Finland under Swedish control and extended the Swedish frontier toward the lands claimed by Novgorod. The castle of Häme, built of stone and brick in the following decades, became one of the centres of Swedish rule in Finland. Birger Jarl is also remembered as the founder of Stockholm.
VIII. The Battle on the Neva
In 1240 a Swedish army, possibly with Norwegian and Finnish troops, landed at the mouth of the Neva, near the later site of St Petersburg. According to the Russian chronicles, they were attacked and defeated by the young prince Alexander of Novgorod, who received the name Nevsky from the victory. The Russian chronicles present the battle as a defence against a Latin crusade, and the Life of Alexander Nevsky describes the Swedish leader as the king of Rome from the northern land, intending to conquer Novgorod.
The Swedish sources do not mention the battle, and its scale is uncertain. Some historians believe it was a minor clash. But the battle, together with Alexander's victory over the Teutonic Knights on Lake Peipus in 1242, as described in the site's page on the Livonian Crusade, became a central part of Russian national memory, and Alexander was canonised by the Russian Orthodox Church.
IX. The Karelians
The Karelians, living between the Gulf of Finland and Lake Ladoga, were contested between Sweden and Novgorod. They traded with Novgorod and paid tribute to it, and many were baptised into the Orthodox faith. They also raided Swedish Finland and the Swedish coast. In 1227 Prince Yaroslav of Novgorod baptised many Karelians, according to the Novgorod chronicle.
The religious division between Sweden and Novgorod gave the conflict over Karelia a crusading character. The papacy regarded the Orthodox Russians as schismatics and the Karelians who followed them as heretics or pagans. The Swedish wars against Karelia and Novgorod were authorised as crusades, while the Novgorodians saw them as attacks on the Orthodox faith.
X. Torgils Knutsson and Viborg
The third Swedish crusade was led in 1293 by Torgils Knutsson, the marshal of Sweden, who ruled for the young King Birger Magnusson. He led an expedition to western Karelia and founded the castle of Viborg, now Vyborg, on an island at the head of a bay. The Chronicle of Eric describes the expedition as a crusade to convert the Karelians, and Pope Boniface VIII granted it crusade privileges. Viborg became the main Swedish fortress on the eastern frontier.
In 1300 Torgils led another expedition to the Neva, where the Swedes built a fortress called Landskrona at the mouth of the Okhta. The Novgorodians took and destroyed it the following year. Torgils was executed in 1306 by King Birger, after a political struggle. The conflict between Sweden and Novgorod continued, with raids and counter-raids in Karelia and Finland.
XI. The Treaty of Nöteborg
On 12 August 1323, Sweden and Novgorod concluded the Treaty of Nöteborg, known in Finnish as Pähkinäsaari and in Russian as Orekhov, at the fortress on an island at the source of the Neva from Lake Ladoga. The treaty fixed the border between Sweden and Novgorod, running from the Gulf of Finland northwest to the Gulf of Bothnia, though the northern part of the border was vague. Western Karelia, with Viborg, went to Sweden, while eastern Karelia, with Käkisalmi, remained with Novgorod.
The treaty divided Karelia between the Latin and Orthodox churches, a division that shaped the region's religious and cultural history. The western Karelians became Catholic and later Lutheran, while the eastern Karelians remained Orthodox. The treaty marked the end of the Swedish crusades in Finland, though conflict with Russia continued in later centuries.
XII. Magnus Eriksson's Crusade
In 1348–1351 King Magnus Eriksson of Sweden undertook a crusade against Novgorod, seeking to convert the Russians to the Latin faith. He invited the Novgorodians to a debate on religion, and when they refused, he attacked. He took the fortress of Orekhov in 1348 and attempted to force the Karelians and Ingrians to accept Latin baptism, but the Novgorodians retook the fortress in 1349, and the crusade failed.
St Birgitta of Sweden, the visionary, supported the crusade and wrote of it in her revelations, but she later criticised the king for his conduct of it. The failure of Magnus's crusade ended Swedish attempts to convert Russia by force.
XIII. The Church in Finland
The church in Finland developed slowly. The cathedral of Turku, consecrated in 1300, became the centre of the diocese. The Dominicans founded a convent in Turku in 1249, and the Bridgettines founded the convent of Naantali in 1438. Parishes were founded in southwestern Finland and Tavastia, and stone churches were built, many of which survive. The school of the cathedral produced clergy, and some Finns studied at universities in Paris and Prague.
The most important figure of the late medieval Finnish church was Bishop Magnus Tavast, who served from 1412 to 1450 and who made a pilgrimage to Jerusalem. He reformed the diocese, built churches and promoted education.
XIV. Mikael Agricola
The Reformation came to Finland under the Swedish king Gustav Vasa in the 1520s. Mikael Agricola, a Finnish student of Luther and Melanchthon at Wittenberg, became the father of written Finnish. He published an ABC book in about 1543, a prayer book in 1544 and a translation of the Greek Scriptures in 1548, the first major work in Finnish. He became bishop of Turku in 1554 and died in 1557 while returning from negotiations with Russia at Moscow.
Agricola's translation gave the Finns the Greek Scriptures in their own language for the first time, four centuries after the legendary crusade. The full Finnish Bible appeared in 1642. The contrast between the conversion of the Finns by the sword and the gift of the Scriptures in their own language is striking. The Greek Scriptures were written to be read and understood (Colossians 4:16), and Paul wrote that he would rather speak five words with understanding than ten thousand in a tongue (1 Corinthians 14:19).
XV. The Sámi
The Sámi of northern Finland, Sweden and Norway were the last people of the region to be Christianised. The Swedish crown and church made efforts to convert them from the sixteenth century, building churches and holding markets. In the seventeenth century the Swedish authorities pursued a vigorous campaign against Sámi religion, destroying sacred drums and punishing those who kept the old practices. The conversion of the Sámi was completed only in the eighteenth century.
XVI. Sweden's Rule in Finland
The Swedish crusades brought Finland under Swedish rule for six centuries, until 1809, when it was conquered by Russia. Finland was an integral part of the Swedish kingdom, not a colony, and its people took part in the election of the king and later in the diet. Swedish became the language of administration and the upper classes, and a Swedish-speaking population settled along the coast. Finnish remained the language of the majority.
Under Russian rule, Finland became an autonomous grand duchy, and in 1917 it became independent. The Finnish national awakening of the nineteenth century looked back to the time before the crusades, celebrating the Kalevala, the epic compiled by Elias Lönnrot in 1835 from Finnish and Karelian folk poetry, as a record of the ancient Finnish culture.
XVII. Crusade or Conquest
Historians debate whether the Swedish expeditions to Finland should be called crusades. The term was not used by contemporaries in the modern sense, and the evidence for the first crusade is legendary. The second and third expeditions had papal support and crusading privileges, but they were also wars of conquest, motivated by trade, security and the rivalry with Novgorod. Some Finnish historians prefer to speak of the Christianisation and the integration of Finland into the Swedish kingdom rather than of crusades.
Whatever the label, the Swedish wars in Finland combined religion and power in a way that the Greek Scriptures do not support. Jesus taught his disciples that they were not to lord it over others as the rulers of the nations did (Mark 10:42-44), and he refused the kingdoms of the world when they were offered to him (Matthew 4:8-10).
XIX. The Chronicle of Eric
The main Swedish source for the second and third crusades is the Chronicle of Eric, a rhymed chronicle in Swedish written about 1320–1335, which covers Swedish history from the mid-thirteenth century to 1319. It was written for the circle of Duke Eric Magnusson, the brother of King Birger, and it presents the Swedish nobility and its chivalric deeds in the style of the courtly romances.
The chronicle describes the expedition of Birger Jarl to Tavastia and that of Torgils Knutsson to Karelia as crusades to spread the faith. It describes the Tavastians and Karelians as heathens and the Russians as enemies of the faith. The chronicle is a valuable source, but it was written decades after the events it describes, and its account of the crusades reflects the ideals and interests of the Swedish aristocracy of the early fourteenth century.
XX. The Novgorod Chronicle
The First Novgorod Chronicle records the conflict from the Russian side. It describes Swedish attacks on Novgorod's territory, the battle on the Neva, the founding and destruction of Landskrona, and the raids of the Karelians. It records the baptism of the Karelians by Novgorod in 1227 and the construction of fortresses on the frontier. The chronicle presents the Swedes as aggressors and the defence of Novgorod as a defence of the Orthodox faith.
The two chronicles together show how the same events could be seen as a crusade by one side and as an invasion by the other. Neither side spoke for the Finns or the Karelians, whose voices are largely missing from the written record.
XXI. Archaeology of Christianisation
Archaeology provides evidence of the Christianisation of Finland independent of the written sources. In southwestern Finland, burial customs changed in the eleventh and twelfth centuries, from cremation with grave goods to inhumation oriented east-west without grave goods, which suggests Christian influence before the Swedish crusades. Crosses, crucifix pendants and other Christian objects have been found in graves. Some of these show Byzantine or Russian influence, indicating that Christianity reached Finland from the east as well as the west.
This evidence suggests that the Christianisation of Finland was a gradual process, beginning before the crusades and continuing long after them. The crusades may have accelerated the process and brought Finland under Swedish political control, but they did not begin it.
XXII. Castles and Frontier
The Swedish rule in Finland was secured by three great castles: Turku Castle in the southwest, Häme Castle in Tavastia and Viborg Castle in Karelia. Each was the centre of a province, governed by a royal official. The castles were built of stone and brick and were expanded over the centuries. Turku Castle became the residence of the royal governors and, in the sixteenth century, of Duke John, the son of Gustav Vasa.
Viborg was the most important frontier fortress. It was besieged by the Novgorodians in 1294, shortly after its foundation, and by the Russians many times later, including in 1495, when according to a legend that historians regard as unhistorical in its details the Swedish commander Knut Posse used gunpowder to create a great explosion, the Viborg Bang, which frightened the Russians away. Viborg remained Swedish until 1710, when it was taken by Peter the Great.
XXIII. The Ingrians and the Votes
Besides the Karelians, the lands along the Neva and the southern coast of the Gulf of Finland were inhabited by the Ingrians and the Votes, Finnic peoples who were subject to Novgorod. They were drawn into the conflict between Sweden and Novgorod, and Swedish expeditions sought to convert them to the Latin faith. In 1256 the Swedes, with Finnish and Estonian troops, tried to build a fortress on the Narva river, but abandoned it when Alexander Nevsky approached.
The Ingrians and Votes remained Orthodox and under Novgorod. In the seventeenth century, after the Treaty of Stolbovo in 1617, Ingria was ceded to Sweden, and many of the Orthodox inhabitants fled to Russia, while Lutheran Finns settled the land. Peter the Great conquered Ingria in 1703 and founded St Petersburg there.
XXIV. St Birgitta
Birgitta Birgersdotter, St Birgitta of Sweden, who lived from 1303 to 1373, was the most famous Swedish religious figure of the Middle Ages. She was a noblewoman, the mother of eight children, who after her husband's death devoted herself to religious life and received visions, which were recorded in her Revelations. She founded the Order of the Most Holy Saviour, the Bridgettines, with its mother house at Vadstena. She moved to Rome in 1349 and campaigned for the return of the popes from Avignon.
Birgitta at first supported Magnus Eriksson's crusade against Novgorod and gave advice on how to conduct it, insisting that the crusaders should not seek plunder and that the converts should be treated well. When the crusade failed, she blamed the king's sins. Her revelations show how the crusading ideal was combined with an ethic of reform and penance.
XXV. The Lutheran Reformation
The Reformation transformed the church in Finland. Gustav Vasa, king of Sweden from 1523, broke with Rome, confiscated church property and introduced Lutheran teaching. The last Catholic bishop of Turku, Arvid Kurck, drowned in 1522 while fleeing the Danes. The Lutheran reforms were introduced gradually, and the Finnish clergy, led by Agricola and his teacher Martin Skytte, the first Lutheran bishop, adapted the new teaching to Finnish conditions.
The Reformation gave the Finns the Scriptures and the liturgy in their own language, which the medieval church had not done. Agricola's preface to his translation of the Psalms in 1551 contains a list of the old Finnish and Karelian gods, including Ukko, the god of thunder, and Tapio, the god of the forest, and it is one of the most important sources for Finnish pagan religion. Agricola recorded the old gods in order to condemn their worship, but in doing so he preserved their names.
XXVI. The Finnish Language and the Bible
The full Finnish Bible of 1642, the work of a committee led by Eskil Petraeus, established the standard for written Finnish. It was printed in Stockholm at the order of Queen Christina. It was used for over two centuries, and it shaped the Finnish language, as Luther's Bible shaped German. The revision of 1776 remained in use until the twentieth century.
The history of the Bible in Finland shows the importance of translation for the spread of the faith. The crusades brought the Finns under the authority of the church, but it was the translation of the Scriptures that brought the content of the faith to the people. The site's page on Bible Scholarship in Königsberg describes the role of the Lutheran university in training translators for the Baltic peoples.
XXVII. The Gotlanders and the Trade Route
The trade route from the Baltic to Novgorod passed through the Gulf of Finland, along the Neva, across Lake Ladoga and up the Volkhov. It was used by merchants from Gotland, who had a trading station at Novgorod, the Gothic Court, and later by the merchants of Lübeck and the Hanseatic League, who founded the Peterhof there. The control of the route was a major interest of Sweden, Novgorod and the German merchants.
The Swedish expeditions to the Neva and Karelia threatened the trade, and the Hanseatic merchants were often reluctant to support them. The merchants preferred peaceful trade with Novgorod, and they sometimes refused to join the trade boycotts that the papacy and the Swedes tried to impose. The conflict between commercial and crusading interests, seen also in the Fall of Acre and the papal trade ban on Egypt, appeared in the north as well.
XXVIII. The Danes in the Gulf of Finland
Denmark also had interests in the Gulf of Finland. The Danish conquest of northern Estonia in 1219, described in the site's page on the Livonian Crusade, gave Denmark control of the southern shore, opposite Finland. Danish kings may also have made expeditions to Finland in the late twelfth and early thirteenth centuries, and the Danish Census Book of King Valdemar contains an itinerary of a sea route from Denmark along the Swedish coast and across to Tallinn, which passes the Finnish coast.
The rivalry between Sweden and Denmark in the eastern Baltic continued throughout the Middle Ages. The Kalmar Union of 1397 united the three Scandinavian kingdoms under one ruler, but it was weakened by conflict, and Sweden broke away under Gustav Vasa in 1523.
XXIX. Lalli in Finnish Memory
The figure of Lalli, the killer of Bishop Henry, has had a long afterlife in Finnish culture. In the medieval legend and the church's teaching, he was a villain, punished by God. In the folk poetry he was sometimes presented with more sympathy. In the nineteenth and twentieth centuries, as Finnish nationalism developed, Lalli was reinterpreted by some as a symbol of Finnish resistance to Swedish domination. Some Finnish writers presented him as a free peasant defending his home against a foreign intruder.
The debate over Lalli reflects the broader debate in Finland over the meaning of the crusades and of Swedish rule. For some, the crusades brought Finland into Western civilisation; for others, they were the beginning of six centuries of foreign rule. Modern historians tend to avoid both extremes, emphasising the gradual nature of the Christianisation and the integration of Finland into the Swedish kingdom.
XXX. The Image of Bishop Henry
Bishop Henry's image appears throughout medieval Finnish art, in church paintings and sculptures, often shown standing on the prostrate figure of Lalli. A great brass cenotaph was made for him in the church of Nousiainen, where his remains were first buried, about 1430. The cenotaph shows scenes from his legend, including the crusade, the baptism of the Finns and his death on the ice. His relics were moved to Turku Cathedral, and after the Reformation they were lost, though some fragments are said to survive. Bishop Henry's feast on 19 January remained an important day in Finland.
XXXI. Peasants and Tithes
The Christianisation of Finland brought new obligations for the population. The church required tithes, paid in grain, furs or other goods, and the crown required taxes. The Tavastians and Karelians, who had paid tribute to no one or to Novgorod, now paid to the Swedish crown and the bishop of Turku. Disputes over tithes were common, and the bishops negotiated with the peasants over the rates, sometimes accepting fixed payments instead of a full tenth.
Unlike the peoples of Livonia and Prussia, the Finnish peasants were not reduced to serfdom. They remained free farmers, owning their land and taking part in local assemblies. This difference, which reflected the nature of the Swedish kingdom, where the peasants had a political voice, distinguished the Finnish experience from that of the peoples conquered by the military orders. In Finland there was no military order and no foreign landed nobility on the scale of Livonia.
XXXII. Finland and the Military Orders
The military orders played almost no role in the Swedish crusades. The Hospitallers had a house at Eskilstuna in Sweden, and the Teutonic Order had small possessions, but no order built castles or conquered land in Finland. The crusades were conducted by the Swedish crown and nobility, with the support of the church. The site's page on the Crusader States and Military Orders describes the orders in the Holy Land, and the pages on Livonia and Prussia show how different the Baltic experience was where the orders ruled.
XXXIII. Summary
The Swedish crusades in Finland are among the least documented of the crusades. The first rests on legend, the second on a late chronicle and the third on a combination of chronicle and papal letters. Yet their outcome is clear: Finland was brought into the Latin church and the Swedish kingdom, and the border with Orthodox Russia established in 1323 shaped the region for centuries.
XXXIV. The Finnish Clergy Abroad
By the late Middle Ages the Finnish church had become an established part of Latin Christendom. Finnish students studied at the universities of Paris, Prague, Leipzig and Rostock, and some of them returned to serve as canons of Turku Cathedral or as bishops. The cathedral library and the Dominican convent of Turku held manuscripts of the Scriptures and of theological works. A few Finns became prominent in the wider church. The Finnish students who went abroad brought back new learning, new books and new ideas about the reform of the church, and in the sixteenth century it was a Finnish student at Wittenberg, Mikael Agricola, who would give the Finns the Scriptures in their own language.
XXXV. Chronology
In 1164 the archbishopric of Uppsala was founded. In about 1156–1160 Eric IX ruled, and the legendary first crusade occurred. In about 1171 Alexander III wrote about the Finns. In 1187 Sigtuna was sacked. In 1209 Innocent III mentioned a bishop in Finland. In 1227 Yaroslav baptised Karelians. In 1229 the bishop's seat was moved. In 1237 Gregory IX called for a crusade against the Tavastians. In 1240 the battle on the Neva was fought. In 1245 Bishop Thomas resigned. In 1249 Birger Jarl went to Tavastia.
In 1293 Torgils Knutsson founded Viborg. In 1300 Turku Cathedral was consecrated, and Landskrona was built. In 1301 Landskrona was destroyed. In 1306 Torgils was executed. On 12 August 1323 the Treaty of Nöteborg was concluded. In 1348–1351 Magnus Eriksson's crusade took place. In 1548 Agricola's translation of the Greek Scriptures was published. In 1642 the full Finnish Bible was published. In 1809 Finland passed to Russia.
XXXVI. Bibliography
The following studies, editions and reference works underlie this account.
Christiansen, Eric. The Northern Crusades. 2nd ed. London: Penguin, 1997.
Lind, John H., Carsten Selch Jensen, Kurt Villads Jensen and Ane L. Bysted. Denmark and the Crusades and the Baltic. Leiden: Brill, 2012.
Heikkilä, Tuomas. Pyhän Henrikin legenda. Helsinki: SKS, 2005.
Lindkvist, Thomas. "Crusades and Crusading Ideology in the Political History of Sweden, 1140–1500." In Crusade and Conversion on the Baltic Frontier, ed. A. V. Murray, 119–130. Aldershot: Ashgate, 2001.
Line, Philip. Kingship and State Formation in Sweden, 1130–1290. Leiden: Brill, 2007.
Fonnesberg-Schmidt, Iben. The Popes and the Baltic Crusades, 1147–1254. Leiden: Brill, 2007.
Grokipedia. First Swedish Crusade.
Grokipedia. Treaty of Nöteborg.