 He was the oldest son of Bernard, Duke of Świdnica, by his wife Kunigunde, daughter of Władysław I the Elbow-high, Duke of Kuyavia and, from 1320, King of Poland.Like his grandfather, King Elbow-high, Bolko II was of small stature; his nickname, "the Small" ("Mały"), reflects this and was used in contemporary sources.After the death of his father in 1326, Bolko II, with his younger brother Henry II as co-ruler, succeeded him in all his domains.