von Diest

The von Diest were a noble house of Brabant, named after their seat at Diest, where Otto von Diest was recorded around 1099. They became lords of Diest and burgraves of Antwerp. Arnold I helped found Averbode Abbey in 1135, and Arnold III gave land to the Teutonic Order in 1229.

Arnold V fought at Worringen in 1288 and held Diest and the Antwerp burgraviate. Although a cleric, his son Johann inherited the family lands and became Bishop of Utrecht in 1322. Heinrich received the Antwerp burgraviate as a fief in 1363, while Wilhelm ruled as Prince-Bishop of Strasbourg from 1393 to 1439.

Thomas fought at Roosebeke in 1382 and acquired Sichem. The direct line ended with Johanna in 1472; through marriage the inheritance passed to the counts of Nassau, reaching Nassau-Diez in 1708.