Ioan James

Ioan Mackenzie James was an English mathematician who worked in topology, above all in homotopy theory, and who also wrote extensively on the history of mathematics. Born in Croydon in 1928, he studied at Queen's College, Oxford, in the topology school of Henry Whitehead, spent 1954 to 1955 in the United States on a Commonwealth Fund Fellowship, and returned to Oxford, where he was Reader in Pure Mathematics from 1957 and held the Savilian Chair of Geometry from 1970 until he retired in 1995. His early papers on fibre spaces and on the homotopy of sphere bundles over spheres were written with Whitehead, and he edited Whitehead's collected works. His books include The Topology of Stiefel Manifolds, Fibrewise Topology and the Handbook of Algebraic Topology, and he was for decades an editor of the journal Topology. He was elected a fellow of the Royal Society in 1968, received the London Mathematical Society's Senior Whitehead Prize in 1978 and served as the Society's president from 1984 to 1986. Later he wrote Remarkable Mathematicians, a collection of sixty biographies. He died in Oxford in 2025.