Adam Loftus (c. 1533 – 5 April 1605) was an English Roman Catholic priest from North Yorkshire who conformed to Anglicanism following the ascension to the throne of Queen Elizabeth I of England.

[2][3] Loftus is also notable, through the marriage of his daughter Anne to the son and heir of Sir Henry Colley and their subsequent issue, as the ancestor of Arthur Wellesley, 1st Duke of Wellington.

He was an undergraduate at Trinity College, Cambridge,[7] where he reportedly attracted the notice of the young Queen Elizabeth, as much by his physique as through the power of his intellect, having shone before her in oratory.

To supplement the meager income of his troubled archbishopric he was temporarily appointed to the Deanery of St Patrick's by the queen in the following year, "in lieu of better times ahead".

Loftus was constantly occupied in attempts to improve his financial position by obtaining additional preferment (he had been obliged to resign the Deanery of St Patrick's in 1567) and was subject to repeated accusations of corruption in public office.

Even though Archbishop O'Hurley revealed that he was not involved in anything except his religious mission and that he had refused to carry letters from the Cardinal Protector of Ireland to the leaders of the Second Desmond Rebellion, Sir Francis Walsingham suggested he should be tortured.

Loftus replied to Walsingham: "Not finding that easy method of examination does any good, we made a command to Mr. Waterhouse and Mr. Secretary Fenton to put him to the torture, such as your honour advised us, which was to toast his feet against the fire with hot boots".

Although the Irish judges repeatedly decided that there was no case against O'Hurley, on 19 June 1584 Loftus and Sir Henry Wallop wrote to Walsingham "We gave warrant to the knight-marshal to do execution upon him, which accordingly was performed, and thereby the realm rid of a most pestilent member".

Due to the unsettled state of the country, Protestantism made little progress in English-speaking or Gaelic Ireland, in direct contrast to the similarly Celtic-language-speaking people of Scotland, the Isle of Man, and Wales.