Theobald Stapleton, (Irish: Teabóid Gálldubh)[1] (1589 – 13 September 1647[1]), was an Irish Roman Catholic priest and one of the creators of modern Irish language orthography. During the Cromwellian conquest of Ireland, Fr. Stapleton sought sanctuary inside St. Patrick's Cathedral upon the Rock of Cashel and was slain by the Protestant army of Lord Inchiquin during the Sack of Cashel. He was Beatified by Pope John Paul II as one of the 17 Irish Catholic Martyrs in 1992.