He was born in a noble family later called Bååt (Old Swedish for boat) originally from Småland, as son of Sune Jonsson, the lawspeaker of Tiohärad, and his first wife Cathrine Henriksdatter Glysing.
In 1320, Erengisle's father Sune and uncle Peter obtained the effectively hereditary position of chatelain of Viipuri castle in easternmost coast of Finland by purchasing it from the governor.
The king's Norwegian tasks for him led to his marriage with an unnamed daughter (possibly Agnes) of Maol Íosa, the Jarl of Orkney (including Caithness), and Earl of Strathearn.
Erengisle became the Orkney Jarl, although there is little evidence that he ever treated it as anything other than a high title, bringing him prestige over the then titleless Swedish nobility; he doesn't even seem to have ever visited his jarldom.
The marriage of Haakon VI of Norway to the daughter of Valdemar IV of Denmark, and Eric's sudden death (from The Plague), drastically changed the political dynamic of Scandinavia, leading Erengisle to be ejected from the Jarldom in 1359.
Haakon chose Alexander de l'Ard, a son-in-law of Maol Iosa, but he proved a disappointment, and was ejected after a few months.
Well-known Bonde magnates, such as High Constable Tord and king Charles VIII, appear to have regarded Erengisle's family as their kinsmen.