Märta Eriksdotter (Bonde) was the alleged daughter of Erik Knutsson, King of Sweden, flourishing in the first half of the 13th century.
[1] Knowledge about her is derived from a genealogy added to a 15th-century copy of the Erikskrönikan.
[2] According to the genealogy she was married to Nils Sixtensson Sparre, a marshal in Sweden,[3] and became the foremother of the noble families of Sparre [sv] and Oxenstjerna.
[1] The genealogy may have been part of King Karl Knutsson's (d. 1470) ambition to prove his right to the throne by presenting a more impressive family background.
[2] Consequently, the existence of Märta and her marriage have been questioned by some modern Swedish historians, who believe she was fabricated by Karl or his chancellery.