Maria Alzira Costa de Castro Cardoso Lemos was born in 1919 in the Portuguese capital of Lisbon. Her father, Fernando de Castro, came from Porto. Her mother, Maria Emília, was from Coimbra, and was the daughter of Afonso Costa, a lawyer, professor and politician, who had campaigned for Portugal to become a Republic and was one of the first Republican deputies during the monarchy and, subsequently, a government minister on several occasions. At the time of her birth in 1919, her grandfather was leading the Portuguese delegation at the Versailles Peace Conference. After the authoritarian Estado Novo dictatorship, which governed Portugal from 1926, came to power Costa was banned from entering Portugal and lived in exile in Paris. Lemos wrote that she had spent all her childhood and adolescence in expectation and in hope for a revolution that would allow not only the return of freedom to Portugal but also allow her family to get together. Her paternal grandfather, Elísio de Castro, was also a Republican, who played an active role with those who tried to overthrow the Estado Novo.