Matthew forcibly abducted the nun Marie de Boulogne, daughter of Stephen, King of England, and constrained her into marriage, claiming the title of Count of Boulogne jure uxoris in 1160.

The forced marriage was opposed by the Church and finally annulled in 1170, but he continued to rule as count until his death.

[1] Maud married Henry I, Duke of Brabant.

[3] Matthew was a supporter of Henry the Young King,[4] and received lands in England.

He died fighting at the siege of Driencourt,[5] during the 1173–74 revolt of Henry II of England's sons, under the leadership of Philip of Flanders.