Born in apartheid South Africa, Duke began writing as a trainee journalist in his teens for The Springs Advertiser in 1964.

In 1973, Duke moved to the UK, where he continued to write anti-apartheid pieces for Argus Newspapers (now Independent News and Media).

Leaving publishing in 1980, Duke began working as a public relations executive for British Transport Hotels.

[2] Duke was involved in the Anti-Apartheid Movement and on arriving in the UK as a refugee from South Africa continued supporting the African National Congress.

Duke strongly opposed the Nationwide Festival of Light, and worked alongside The Freethinker and National Secular Society to try to counter its effects and influence.