Duke of Finland

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Duke of Finland (Finnish: Suomen herttua; Swedish: hertig av Finland) was an occasional medieval title granted as a tertiogeniture to the relatives of the King of Sweden between the 13th and 17th centuries. It included a duchy along with feudal customs.

Starting with John III in the 1580s, Swedish monarchs adopted the style of Grand Duke of Finland. This title was used until 1720, revived in 1802–1805, and later adopted by the Russian emperors during the period of the Grand Duchy of Finland (1809–1917).

In the late 15th century, historian Ericus Olai referred to Bishop Kol of Linköping (died about 1196) as Duke of Finland (Colo episcopus Lincopensis et dux Finlandie).^[1] The title is anachronistic: in the late 12th century in Sweden, the Latin title "dux" was still used in the meaning of jarl and came to mean duke only a hundred years later (see Swedish duchies).^[2] Ericus Olai's claim is not supported by other sources.

Per Olof Sjöstrand has suggested that the title should be understood in relation to the activities in the eastern Baltic for which the Bishop of Linköping was responsible. In 1229, the Pope used him to assist the Bishop of Finland in organizing the diocese, and the first known Duke of Finland, Bengt, was later elected Bishop of Linköping. The Bishop of Linköping had also accompanied the Swedish ledung on their unsuccessful Estonian expedition in 1220. Birger Jarl, who led the second crusade to Finland, was likewise closely associated with the Bishop of Linköping through family ties.^[3]

Bengt Birgersson (1254–1291), a clergyman and the youngest son of Birger Jarl, was granted the title of Duke of Finland (dux Finlandiae) around 1284 by his brother, King Magnus Ladulås, whom he had supported in his rebellion against their eldest brother. In practice, Bengt's ducal authority appears to have been largely titular and did not involve a specified territory. Bengt was elected Bishop of Linköping in 1286 and remained occupied with his duties related to that office. Although he retained the revenues associated with the duchy until his death in 1291, there is no evidence that he ever visited Finland or exercised independent rule there.^[4]

Valdemar (d. 1318), the youngest son of King Magnus Ladulås (1240–1290), was granted the Duchy of Finland as an appanage at the coronation of his elder brother King Birger in 1302. Birger’s instructions to the castellan of Turku from 1303 show that Valdemar held administrative responsibilities in Finland, even if he did not reside there.^[5]

Conflict between King Birger and his brothers, dukes Erik and Valdemar, broke out in 1304, and the king took control of all Finnish castles. Valdemar thereafter styled himself Duke of Sweden rather than of Finland, though he continued to use an earlier seal naming him as Duke of Finland. By 1310–1314, the realm had been divided between the king and the dukes. In Finland, Turku and Häme castles were administered jointly by the dukes. In 1315, the dukes divided their territories. Valdemar received the eastern part, which included Turku and Häme castles, Stockholm, part of Uppland, and Öland. He established his ducal court at Borgholm in Öland.^[5]

In December 1317, King Birger had his brothers seized at the Nyköping Banquet. Both dukes died the following year while imprisoned. With his second wife, Ingeborg Eriksdotter, Valdemar had a son born in 1316 who died young.^[6]

Lord Bengt Algotsson (1330–60), accused for political reasons by Saint Bridget of being a homosexual lover of King Magnus IV of Sweden (nephew of Duke Valdemar above), had already in 1353 been recognized as Duke of Halland, originally a Danish principality, and in 1353 or 1354 also was given the Duchy of Finland.

The Duke apparently never seriously attempted to establish himself as ruler of Finland, being satisfied to bear revenues from the duchy. He had his seat in Southern Sweden, where he also acted as Viceroy of Scania.

The Duke became the victim of certain nobility's opposition to King Magnus, was exiled in 1357, and killed without an heir in 1360. In 1357, his holdings, including Finland, had been given (without the title) to King Eric, then co-ruler with Magnus. Eric did not need the ducal title, and it was then vacant almost 200 years.

In 1556, two hundred years after it was vacated by the removal of Duke Bengt Algotsson, King Gustav I of Sweden (reigned 1523–1560) gave the Duchy of Finland to his second son, the then 18-year-old Prince John (1537–1592). John was the only holder of the title to establish a genuine princely rule of his own in Finland. The duchy included the Southwest Finland, Raseborg together with Western Uusimaa, and Lower Satakunta. The duchy thus formed was given extraordinarily independent feudal rights by the King. Additionally, John was appointed Governor-General of Finland, including all the other areas beyond the Gulf of Bothnia and up to the eastern border. Those areas were however not held by feudal right but with John as a royal appointee.

Duke John settled in Turku, where he created a cultivated princely court at the Turku Castle. He was an enthusiastic patron of arts and architecture and decorated the castle with splendor never before seen in Finland. Before his marriage, he had a Finnish mistress, Karin Hansdotter. Several Finnish and Swedish families claim descent from their offspring. After the death of his father, John ran his own foreign policy which at times was at odds with his elder brother King Eric XIV of Sweden (reigned 1560–1568). In domestic affairs too, John soon opposed the King, together with a party of high nobility who all were against an increasing centralization of the government. On October 4, 1562, against the wishes of the King, John married his first wife Princess Catherine Jagellonica (1526–1583), daughter of King Sigmund I of Poland (1467–1548). Eric regarded this conduct as rebellion. John and Catherine were imprisoned at Gripsholm Castle the year after their wedding and after a siege of Turku Castle and its conquest by royal troops. The imprisoned Duke considered himself to have kept his title, while the duchy itself was administered by royal officials.

Eric was deposed by John, who had been released, acting with leaders of the nobility in 1568, and John and ascended the throne of Sweden, reigning until his death in 1592 as King John III. In 1589 he appears to have made arrangements to grant the Duchy of Finland at birth to his younger son Duke John (see below).

In 1581, King John III additionally assumed the subsidiary title of Grand Prince of Finland and Karelia.^[7] Karelia was soon dropped from the title and considered part of Finland in an expanded eastern extent. The title became established in Latin renderings, and later in the 19th century also in English, as Grand Duke of Finland, however using the Finnish (ruhtinas) and Swedish (furst), for a crowned or sovereign prince, in its local renderings.

Shortly before his death, King John III, the previous Duke of Finland, gave his old Duchy and its title as a royal duke to John the Younger (1589–1618), his newborn son in a second marriage to Gunilla Bielke (1568–1597). King Sigmund (III) of Poland and Sweden, half-brother of John the Younger, seems to have confirmed this appanage.

A royal chancellery administered the duchy on behalf of the child-duke and provided him with his allotted revenues. However, when Duke John approached adulthood, his duchy was exchanged in 1606 for that of Östergötland which previously had been held by King John's brother, the late Duke Magnus. Duke John the Younger married his first cousin Princess Maria Elisabeth of Sweden (1596–1618). They died childless.

From 1590 to 1599 John's father and half-brother (as most subsequent monarchs until 1720) continued to call themselves Grand Dukes of Finland.^[8]

Crown Prince Gustavus Adolphus (1594–1632), elder son of Charles IX of Sweden, as heir apparent was made Duke of Finland in 1606, while Östergötland was assigned to his cousin Duke John the younger instead. Gustavus Adolphus then started to receive ducal revenues from Finland. When he ascended the throne of Sweden in 1611 he readopted^[9] Grand Duke of Finland among his titles. He was the last to have a real feudal principality of Finland and revenues therefrom.

This list includes Swedish lords of Finland by other titles.

Title held (years)	Name	Notes
1284-1291	Bengt Birgersson	appointed, also Bishop of Linköping, died with title
1302-1318	Valdemar	appointed, also Duke of Uppland & Öland from 1310, died with titles
1302-1305	Christina	as first wife of Waldemar above, until divorce
1312-1353	Ingeborg	as second wife and widow of Valdemar above, deposed, continued as Duchess of Öland in her own right, died c.1357
1353-1357	Bengt Algotsson	appointed, deposed, also Duke of Halland until 1356, died c.1360
1364–1395	Albert	son of Albert II and Euphemia became King of Sweden and Finland from 1364–1395 and Duke of Mecklenburg-Schwerin from 1384–1412
1465-1467	Charles	appointed Lord of Finland, became King of Sweden and Finland again in 1467, died in 1470
1556-1563	John	appointed, deposed, became King of Sweden & Finland 1569, died 1592 (see below King John III)
1562-1563	Catherine	as (first) wife of Prince John above, deposed, became queen in 1569, died in 1583
1589-1606	John	from birth, deposed, continued as Duke of East Gothland, died with that title 1618
1580s-1599	Kings John III & Sigmund	as monarchs also held the nominal title of Grand Duke of Finland, simultaneously with John just above
1606-1632	Gustav Adolph	appointed, also Duke of Estonia 1607-1618, Södermanland 1604-1607 & Västmanland 1610-1611, became King of Sweden and Finland in 1611 and then also maintained title Grand Duke of Finland, died with it
1632-1720	Swedish rulers	Christina, Charles X Gustav, Charles XI, Charles XII & Ulrica Eleanor as monarchs also all held the nominal title of Grand Duke of Finland
1802-1805	Carl Gustav	from birth Great Duke of Finland, died with title
1809-1917	Russian rulers	Alexander I, Nicholas I, Alexander II, Alexander III & Nicholas II as emperors also all held the nominal title of Grand Duke of Finland

• Monarchy of Finland
• Grand Duchy of Finland
• Duchies in Sweden
• List of heads of state of Finland
• Governor-General of Finland

• Sjöstrand, Per Olof (1994). "Den svenska tidigmedeltida statsbildningsprocessen och den östra rikshalvan". Historisk Tidskrift för Finland (in Swedish). 79: 530–573.
• Line, Philip (2007). Kingship and State Formation in Sweden, 1130–1290. Brill.