Bo Jonsson Grip

Bo Jonsson (Grip) (early 1330s – 20 August 1386) was head of the royal council and marshal under the regency of Magnus IV of Sweden. Also in the council was his friend and colleague, Karl Ulfsson av Ulvåsa, eldest son of Saint Birgitta. From 1369, during Albert of Sweden’s reign, he was Officialis Generalis (the king's highest official) and from 1371 Lord High Steward (drots in Swedish).

Bo Jonsson dominated the political life of Sweden and Finland for decades. He was the most influential representative to the council of aristocracy that deposed Magnus IV of Sweden in 1365 and installed Albrecht von Mecklenburg on the Swedish throne. His position as the new king's Officialis Generalis granted him vast fiscal and administrative control. By 1374, he had gained title to all of Finland.

The family name, Grip − which Bo Jonsson himself never used −, is Swedish for Griffin. A coat of arms showing a black griffin on a gold shield, attributed to Bo Jonsson, was later adopted as the coat of arms of Södermanland. The original family arms, however, may have been Argent, a griffin's head sable, traced back to Tomas Jonsson (Grip) from around 1299.

Through inheritance and unprejudiced methods, Bo Jonsson came to control the largest private non-royal wealth Sweden has ever seen. He usurped 1,500 farms in 350 parishes throughout Sweden, from Kalmar to Falun, through economic and political means. He became Sweden's (and Finland's) largest landowner ever. The quantity of land under his control exceeded 1/3 of the entirety of the Swedish realm, surpassing even the ruling king's national land holdings. In 1363 he was the leader of an aristocratic rebellion. He solicited support from Albert II, Duke of Mecklenburg and in 1365, he became instrumental in removing Magnus Eriksson from the Swedish throne and offering it to the Duke's son.

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