Willem Eggert

He owned much land in Weesp, Monnickendam, Oosthuizen, Aalsmeer and Wognum.

In 1410 Eggert was styled 1st Lord of the free and high fief Purmerend and Purmerland.

In the same year he was allowed, by count William VI of Holland, to build his own fortified castle, Slot Purmerstein.

He played an important role during the reign of William VI, including in the conclusion of a three-year peace with the Frisians in 1414.

His daughters: Jennette Eggert married Reinout van Brakel originally from Geldern, who was appointed Baljuw of Amstelland, Aleid Eggert married to Gerrit van Zijl from Utrecht, and Lijsbeth Willemsdr (also named Imme) Eggert married Willem de Grebber.