Constance of Greater Poland

Constance of Greater Poland (also known as of Poznań) (Polish: Konstancja wielkopolska (poznańska)) (1245/46 – 8 October 1281) was a princess of Greater Poland, a member of the House of Piast, and by marriage a Margravine of Brandenburg–Stendal.

She was the eldest daughter of Przemysł I, Duke of Greater Poland and Poznań, by his wife Elisabeth, daughter of Henry II the Pious, Duke of Wrocław. She was probably named after her maternal aunt Constance, second wife of Casimir I, Duke of Kuyavia.

In 1255 Constance was engaged to Conrad, son of , Margrave of Brandenburg. On 19 December of that year, Pope Alexander IV gave her a dispensation to celebrate the marriage, which was necessary because both Constance and Conrad were great-great-grandchildren of Mieszko III the Old (Constance through Mieszko III's son Odon and Conrad through Mieszko III's daughter Elisabeth). With this alliance, Duke Przemysł I and his brother Bolesław the Pious wanted to establish warmer relations with expanding Brandenburg, which became dangerous to the Greater Poland Dukes during the 1250s.

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