Complex sentence: Wellington was born in Ireland as "The Honourable Arthur Wesley", the fourth son--third of five surviving sons--to Garret Wesley, 1st Earl of Mornington, and Anne, the eldest daughter of Arthur Hill-Trevor, 1st Viscount Dungannon.
Split into simpler sentences: Wellington was born in Ireland as "The Honourable Arthur Wesley". The fourth son--third of five surviving sons--to Garret Wesley, 1st Earl of Mornington, and Anne, the eldest daughter of Arthur Hill-Trevor, 1st Viscount Dungannon.