Matilda of Flanders exercised authority as duchess of Normandy after marrying William around 1050. Her family connections strengthened the alliance between Normandy and Flanders, while her role extended to charters, religious patronage and government during William's absences. She and William established major religious houses at Caen; her foundation of Sainte-Trinité, the Abbaye aux Dames, became closely associated with her household and her daughter Cecilia.

While William invaded England in 1066, Matilda remained in Normandy and helped administer the duchy. She crossed to England in 1068 and was crowned at Westminster on May 11. Her position as queen brought substantial lands and revenues, and her name continued to appear in legal instruments. She traveled between the two territories but spent much of her time in Normandy, combining regency with ceremonial and dynastic duties. Her children included Robert Curthose and the future English kings William II and Henry I.

Family loyalties complicated this partnership. When Robert rebelled against William in the late 1070s, Matilda secretly sent him financial support, angering the king when he learned of it. She subsequently sought reconciliation between father and son. Her religious patronage continued until her death in 1083, and she was buried at Sainte-Trinité in Caen. The familiar tradition that she and her ladies embroidered the Bayeux Tapestry arose later; its production cannot securely be attributed to her.