Jacob, Banner Lord of Wassenaer, Lord Obdam, Hensbroek, Spanbroek, Opmeer, Zuidwijk and Kernhem (1610 – 13 June 1665) was a Dutch nobleman who became lieutenant admiral, and supreme commander of the navy of the Dutch Republic. The name Obdam was then also spelled as Opdam. British contemporaneous sources typically refer to him as Admiral Opdam or Lord Obdam because it was not until 1657 that he bought the Wassenaar Estate from relatives and thus acquired its title. Modern Dutch sources sometimes less correctly insert a second "van" between "Wassenaer" and "Obdam" or use the modern spelling "Wassenaar". Early life Jacob was born in 1610, the eldest son of Lieutenant-Admiral Jacob van Wassenaer Duivenvoorde, born 1574, and Anna van Randerode. After early military training, he joined the army and, in 1631, commanded a company of cavalry, soon rising to the rank of colonel. In this capacity, he took part in several sieges and was commended for his bravery fighting against the Spanish at the siege of Maastricht in 1632, and in 1643 he became drost (political governor) of Heusden, an important fortress town, and soon after military governor of its garrison. In 1647, when the provinces of Gelderland and Overijssel proposed peace with Spain, Van Wassenaer was delegated by the majority of provinces that wished to continue the war in alliance with France to visit the two provinces, and he succeeded in convincing them to continue to fight. In 1648, in another mission on behalf, this time, of all the Netherlands provinces, he attended the baptism at Kleve of the eldest son of Frederick William of Brandenburg, and in 1651 he visited Frederick William at Düsseldorf to discuss a possible military alliance. On 28 April 1633, at Maarssen, he married Agnes Renesse van der Aa and had three children by her. First Anglo-Dutch War As a member of the nobility of Holland, van Wassenaer was delegated to the States of Holland to represent their interests as one of the ten members of the ridderschap (the "knighthood" Estate within the States). In 1650 when stadtholder William II of Orange died, he opposed installing the latter's infant son as nominal stadtholder. His opposition to the House of Orange was based on socio-economic and religious grounds: the stadtholders had their political base in the artisan class, which consisted mainly of puritan Calvinists. Many members of the van Wassenaer family were still Catholic and feared