Gregers Birgersson

Gregers Birgersson (died 15 January 1276), also known as Gregorius, was a Swedish knight and landowner. He was an illegitimate son of Birger Jarl of the House of Bjälbo and an unknown woman, and was therefore a grandson of Magnus Minnesköld and Ingrid Ylva.

Evidence that Birger Jarl had an illegitimate son named Gregers comes from a notice of Gregers's death in excerpts made by the 17th-century Danish historian Otto Sperling from a now-lost copy of an Icelandic annal. The relationship is also supported by a charter dated 27 March 1272, issued by a man described as G quondam ducis filius ("G., son of the late duke"). He was married to a woman whose name is unknown and who apparently owned land in Södermanland.

Children Gregers had at least five children:

Knut Gregersson Magnus Gregersson Karl Gregersson An unnamed daughter, who married Filip Ingevaldsson (Örnsparre) At least one additional unnamed daughter, possibly the mother of Mats Kettilmundsson