Ussher, Ambrose (c.1582–1629), scholar and protestant clergyman, was born in Dublin, the second surviving son of Arland Ussher (d. 1598) and Margaret, daughter of James Stanihurst (qv). He was brother to James Ussher (qv), primate of Ireland and renowned antiquarian. Both laboured in the same discipline but James garnered the acclaim, though he owed much to his less celebrated brother's diligence. Educated at TCD, Ambrose graduated BA in 1601 and MA in 1605, and became a fellow on 7 March 1611; he also studied at Cambridge. His date of ordination is not known, but by 1616 he had two rectories in Co. Louth.
Dedicating himself to a life of study within the walls of TCD, he became one of the most learned Hebrew and Arabic scholars of his time. His only published work was a catechism for instructing the young, but he left thirty-four works in manuscript, which are held at TCD library; they consist of sermons, theological commentaries, political works, biblical and classical translations, copies of oriental works, and dictionaries of oriental languages. While his translation of the bible from Hebrew, which he dedicated to the king, was finished after the completion of the King James bible, Ussher had started his project much earlier. His career was cut short by his early death; he was unmarried. He was buried on 4 March 1629 at either the college chapel or St Werburgh's, Dublin.