In 1963-4 he spent a gap year with Voluntary Service Overseas (VSO) in Jerusalem, where he worked with handicapped people, some of whom were Holocaust survivors.
Throughout the 1980s, Parfitt undertook covert lecture tours to Jewish Refusenik groups in the Soviet Union and Czechoslovakia.
In 1985 he spent several months visiting the various Jewish communities of Asia - including Thailand, Hong Kong, Singapore and Japan.
In the early 1990s, Parfitt conducted fieldwork in Yemen, researching its ancient Jewish community, and wrote a book on the subject.
In The Road to Redemption, he said that the Yemenite Jews had emigrated to Israel as a result of extreme prejudice, persecution, legal disabilities and because of the rapidly changing economy of the Indian Ocean region.
One of his themes is that the creation of Israelite and Judaic identities throughout the world, from the Americas to Papua New Guinea, was an innate feature of Western colonialism.
His interest in far-flung Jewish Judaising communities has led him to travel to Papua New Guinea, Madagascar and Central and South America.
[6] In 1984 Parfitt was commissioned by the London-based Minority Rights Group to write a report on the Ethiopian Jews who had fled Ethiopia.
They had migrated to escape persecution and famine, but were dying in large numbers in the refugee camps along the border between the Sudan and Ethiopia.
These found a high proportion of paternal Semitic ancestry, DNA that is common to both Arabs and Jews from the Middle East.
In recognition of this work, he was made corresponding fellow of the Académie Royale des Sciences d'Outre-Mer.TV programs about the discoveries, and major newspaper coverage, brought Parfitt international attention.In 2000 e appeared on '60 Minutes' produced by CBS.
Parfitt proposed that the Ark of War may have been taken by Jews across the Jordan River and, citing Islamic sources, suggests that they perhaps carried it as they migrated south, while under rule by Arab tribes.
[10] In 2010 Parfitt was invited to address a symposium in Harare on the subject; attendees included the cabinet and vice-president John Nkomo.
[13] Parfitt's pioneering work has contributed to the expanding study of the spread of Judaism and Judaising movements throughout the African continent.
His widely reviewed book on the history of race as it affects Jews and Blacks — Hybrid Hate: Conflations of Antisemitism & Anti-Black Racism from the Renaissance to the Third Reich — was published by Oxford University Press in 2020.