William John Arthur Charles James Cavendish-Bentinck, 6th Duke of Portland,, known as William Cavendish-Bentinck until 1879, was a British landowner, courtier, and Conservative politician. He notably served as Master of the Horse between 1886 and 1892 and again between 1895 and 1905.

Welbeck Abbey is an English mansion situated in the village of Welbeck, which is within the civil parish of Norton, Cuckney, Holbeck and Welbeck, in the Bassetlaw District of Nottinghamshire. It was the site of a monastery belonging to the Premonstratensian order in England and after the Dissolution of the Monasteries, a country house residence of the Dukes of Portland. It is part of the Dukeries, four contiguous ducal estates in North Nottinghamshire. The house is a Grade I listed building.