When the third Marquis succeeded his half-brother, he found, with the exception of a few family portraits, very few pictures in Lansdowne House, and promptly endeavoured to bring together a fine and representative collection of the works of the old masters. The contemporary records of celebrated painters show that he was a liberal and discriminating patron of the artists of his own time.
He also purchased the collection of sculpture from the widow of the second Marquis which had been left to her by that peer, and which is therefore proved, surprisingly, not to have been an heirloom.