From 1960 to 1962, Luttrell taught at
Swarthmore College in
Pennsylvania, United States. In 1963, he joined the Department of History at the
University of Edinburgh as a lecturer, a position he held for four years. Between 1967 and 1973, he served as assistant director and librarian of the
British School at Rome, before joining the Department of History at the
Royal University of Malta from 1973 to 1976. In 1977–1978, Luttrell was a
visiting fellow at the
School of Historical Studies at the
Institute for Advanced Study,
Princeton University. He then conducted research at the (IRHT) within the
French National Centre for Scientific Research (CNRS) in
Paris before returning to the University of Malta as a lecturer from 1979 to 1980. Luttrell's research on the
Knights of the Order of the Hospital of St John of Jerusalem in
Rhodes and
Malta integrated archival investigation with archaeological studies during the 1970s and 1980s, providing insight into Malta's early and medieval history. Over the course of his career, he has published more than 250 works, including a six-volume collected study published by
Routledge. Widely regarded as the foremost historian of the Hospitallers in the fourteenth and fifteenth centuries, his notable contributions include
Studies on the Hospitallers after 1306: Rhodes and the West (2007),
The Town of Rhodes 1306–1356 (2003) and
Hospitaller Women in the Middle Ages, co-authored with Medieval historian
Helen J. Nicholson (2006). == Recognition and legacy ==