sentences:  In 1812 Catherine took the disastrous step of accepting the marriage proposal from the later-notorious rake, William Wellesley-Pole, nephew of two famous uncles, Richard Wellesley, 2nd Earl of Mornington, eldest brother of his father William, and Arthur Wellesley, Duke of Wellington from 1813, his father's younger brother.The Wellesleys played no part in securing the marriage into their family of this great heiress.Shortly before the wedding Catherine's husband had changed his family surname by Royal Licence to Pole-Tylney-Long-Wellesley.