Bo Jonsson, royal marshal of Sweden

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.