James FitzGerald, de jure 12th Earl of Desmond (died 1540) was the grandson of Thomas FitzGerald, 11th Earl of Desmond. James's father, Maurice, had died of the plague shortly after Thomas attained the earldom, so upon Thomas's death, James inherited it. However, James's title was disputed by his granduncle John FitzGerald, de facto 12th Earl of Desmond. John died in 1536. Although James lived until 1540, he was succeeded by John's son James FitzGerald, 14th Earl of Desmond.
Alfred Webb tells us of this earl that he was "called the 'Court Page,' having been hostage for his grandfather at the court of Windsor. On the earldom becoming vacant in 1534, 'the King loaded him with honours, and fitted out ships to accompany him to the Irish shores, and provided him with a number of men who were ready to stand by him against those who were inclined to dispute his title to the patrimonial honours and inheritance.' His title to the earldom was disputed by his grand-uncle, Sir John, who being supported by a large faction, was de facto [12th] Earl. This Sir John died about Christmas 1536. The 'Court Page' did not long enjoy his honours, for he was murdered at Leacan Sgail in Kerry, by his cousin, Maurice an Totane, son of his late opponent, 19th March 1540. He married a daughter of his grand-uncle, Cormac Oge MacCarthy."
James FitzMaurice FitzGerald wed Mary, daughter of Cormac Óg MacCarthy, and left no issue.