Walter Ullmann was born 29 November 1910 in Pulkau, Lower Austria, the elder son of Rudolf and Leopoldine Ullmann. He attended the Gymnasium at Horn and then the University of Vienna to read jurisprudence, transferring in 1931 to the University of Innsbruck, where he earned a JUD in 1933. He originally practiced criminal law in Germany but had to flee to Britain in 1938, where he was supported by a Cambridge committee for the support of refugee scholars.In 1939 he became master at Ratcliffe College in Leicestershire but during the war he was interned on the Isle of Man with other enemy aliens, and served in the Pioneer Corps. In November 1940 he married Mary Elizabeth Finnemore Knapp, with whom he had two sons. When his book 'The Origins of the Great Schism' was published in 1948, Ullmann was a lecturer at the University of Leeds, and the same year he gave the Maitland memorial lectures in Cambridge, published in 1949 as 'Medieval Papalism'.In 1949 he was appointed to a lectureship at the University of Cambridge, and in 1955 he published what the DNB calls his most important book, 'The Growth of Papal Government in the Middle Ages: a Study in the Ideological Relations of Clerical to Lay Power'. He was awarded a readership in 1957, the LittD in 1958, fellowship of Trinity College in 1959, fellowship of the British Academy in 1968, and the chair of medieval history in 1972. George Garnett in the DNB writes: 'He was probably the most prolific British medievalist since the Second World War, not only in terms of publications but also in terms of research students.' Ullmann retired in 1978, but continued to supervise students until shortly before his death from cancer on 18 January 1983.