Aldona (baptized as Ona or Anna; her pagan name is known only from the writings of the 16th century chronicler Maciej Stryjkowski) married Casimir III of Poland, son of Władysław I of Poland, when he was 15 or 16 years old. The marriage took place on either 30 April or 16 October 1325, and was a purely political maneuver to strengthen the Polish–Lithuanian coalition against the Teutonic Knights (an alliance foreshadowing the Union of Krewo in 1385 and the Union of Lublin in 1569, with the latter resulting in a stable and powerful new state, the Polish–Lithuanian Commonwealth). This preliminary coalition was short-lived, collapsing in about 1330, but there is no evidence of military conflict between Poland and Lithuania while Aldona was alive.