Robert Culshaw was born on 22 December 1952, the son of Ivan Culshaw and Edith Marjorie Jose Barnard. He was educated at University College School, Hampstead and King’s College, University of Cambridge (BA 1st Class Hons Classics 1974; Major University Scholarship for Classics, 1974; MA 1977). In 1977 he married Elaine Ritchie Clegg, having one son.

Culshaw joined the Foreign and Commonwealth Office in 1974 and his diplomatic career included: Central and Southern African Department, FCO, 1974–75; MECAS, Lebanon and Jordan, 1975–77; 3rd Secretary, Muscat [Oman], 1977–79; 2nd Secretary, Khartoum [Sudan], 1979–80; 1st Secretary, Rome [Italy], 1980–84; 1st Secretary, Planning Staff, FCO, 1984-85; Assistant Private Secretary to the Foreign Secretary, 1985–89; Head of Chancery, then Deputy Head of Mission, Athens [Greece], 1989-93; FCO Spokesman and Head of News Department, 1993–95; Minister-Counsellor, Washington [United States], 1995–99; Consul General, Chicago, 1999–2003; Director, Americas and Overseas Territories, FCO, 2003–05. Deputy Director, British Antarctic Survey, 2006-12.