Professor Henry Chadwick (1920-2008) enjoyed international renown as one of the leading church historians of the twentieth century. He held senior appointments at both Oxford and Cambridge Universities, latterly as Emeritus Regius Professor of Divinity, Cambridge. Chadwick's scholarship was complemented by his active involvement in church life. Ordained a priest in the Church of England in 1944, he developed a deep commitment to church unity and took a leading role in the Anglican and Roman Catholic dialogues of the mid-1970s.