The European Radicals in Sri Lanka were Europeans (or Americans) who went against the colonial system prevailing in Ceylon (now Sri Lanka). Their contribution was far greater than their numbers would appear to merit, mainly because of their defiance of the white-supremacist attitude that pervaded the British Empire. Most of them were radical activists in their own countries who married Sri Lankan revolutionary politicians. They were active in the Lanka Sama Samaja Party, the Communist Party of Sri Lanka and the Viplavakari Lanka Sama Samaja Party.
Attempts at deportation were made of several of them, most famously Mark Anthony Bracegirdle, but including Rhoda Miller de Silva, Jeanne Hoban Moonesinghe and Maud Keuneman.
Others were Doreen Young Wickremasinghe, who became a Member of Parliament, Edith Gyömrői Ludowyk and Hedi Keuneman.