Olesk was born in Võru County in South Estonia in 1921. He studied law at the University of Tartu, and continued his education in social sciences at Stockholm University after his escape from Estonia in 1944. He worked as a teacher in the Estonian primary school in Stockholm before relocating to New York in 1956, where he continued in finance. He played an active role in organizing the cultural life of Estonians in exile, and in restoring the independence of Estonia.

Olesk was decorated with the Order of the White Star, 4th Class, in 2005.

Olesk later wrote Globaalne Eesti (Global Estonia), collecting texts written by him over the decades of his work towards the recognition of Estonian culture and independence.

The Ministry of Foreign Affairs remembers Olesk with gratitude for his political contribution to the reestablishment of Estonian independence, a communique read.