Freire enrolled at Law School at the University of Recife in 1943. He also studied philosophy, more specifically phenomenology, and the psychology of language. Freire never actually practiced law but instead worked as a teacher in secondary schools teaching Portuguese. In 1944, he married Elza Maia Costa de Oliveira, a fellow teacher.
In 1946, Freire was appointed Director of the Department of Education and Culture of the Social Service in the State of Pernambuco, the Brazilian state of which Recife is the capital. Working primarily among the illiterate poor, Freire began to embrace a non-orthodox form of what could be considered liberation theology. In Brazil at that time, literacy was a requirement for voting in presidential elections.
In 1961, he was appointed director of the Department of Cultural Extension of Recife University, and in 1962 he had the first opportunity for significant application of his theories, when 300 sugarcane workers were taught to read and write in just 45 days. In response to this experiment, the Brazilian government approved the creation of thousands of cultural circles across the country. In 1964, a military coup put an end to that effort. Freire was imprisoned as a traitor for 70 days. After a brief exile in Bolivia, he worked in Chile for five years for the Christian Democratic Agrarian Reform Movement and the Food and Agriculture Organization of the United Nations. In 1967, he published his first book, Education as the Practice of Freedom. He followed this with his most famous book, Pedagogy of the Oppressed, first published in Portuguese in 1968.