Thomas Newenham Deane

Sir Thomas Newenham Deane (1828 – 8 November 1899) was an Irish architect, the son of Sir Thomas Deane, and father of Sir Thomas Manly Deane, who were also architects.

Born in Cork, he joined his father's practice in 1850 and in 1851 became a partner along with Benjamin Woodward.

Their work was a Gothic style influenced by the principles of John Ruskin, and included the Museum at Trinity College, Dublin, the Oxford University Museum of Natural History, Oxford, the Pitt Rivers Museum, the Kildare Street Club, Dublin and Queen's College Cork, now University College Cork. He is also known as a conservation architect, involved in the restoration (including the incorporation of the original twelfth-century Romanesque chancel) of the St. Mary's Cathedral, Tuam, which was praised by George Petrie. His work on the conservation of St Canice's Cathedral, Kilkenny, was less successful, and brought him into conflict with the dean and chapter, and in particular with the Treasurer James Graves. It may have been due to his interest in the restoration of medieval buildings which led to his appointment as the first Inspector of National Monuments under the Irish Board of Works after the Disestablishment of the Church of Ireland brought ruined buildings under their care. His work included St. Cronan's Church, Roscrea, County Tipperary.