The title Earl of Mornington was created in the Peerage of Ireland in 1760 for Garret Wellesley. On the death of the fifth earl it passed to the dukedom of Wellington, where it has remained. The subsidiary titles associated with this peerage are Viscount Wellesley (1760) and Baron Mornington (1746), both in the Peerage of Ireland.
The second earl, Richard Wellesley, was created Baron Wellesley in the Peerage of Great Britain in 1797 and Marquess Wellesley in the Peerage of Ireland in 1799, which titles became extinct at his death. The third earl had been created Baron Maryborough in the Peerage of Ireland in 1821. This title became extinct on the death of his grandson the fifth earl.
Barons Mornington (1746)
Earls of Mornington and Viscounts Wellesley (1760)
for further succession, see Duke of Wellington
Barons Wellesley (1797) and Marquesses Wellesley (1799)
Barons Maryborough (1821)
de:Earl of Mornington
