Son of Hans Willem Bentinck (1649-1709), 1st Earl of Portland, and Jane Martha Temple. Created Count by Emperor Karl IV in 1732. Married (1733) to Countess Charlotte Sophie von Aldenburg. They divorced in 1740. Father of Christian F. A. van Bentinck and John Bentinck (1737-1775), a sometime naval officer, inventor and English MP.
Bentinck was a staunch Orangist and a favourite of William IV (1711-1751). However, even though he was instrumental in putting the regency of Princess Anne (1709-1759) in place for her infant son, William V of Orange, as hereditary stadtholder-general in the Dutch Republic, he soon lost influence and never regained the position he had at the court of William IV.
Boswell went with Arend van Reede to visit the Comte de Rhoon1 on April 28, 1764. Boswell described him as "polite; great man of business in Dutch affairs".