Castellina was born in
Rome on 9 August 1929. She graduated in law from
Sapienza University of Rome. In 1947, she joined the
Italian Communist Party. Castellina started her career in journalism in the 1950s, working for the daily newspaper
Paese Sera. She later worked for several other newspapers, including ''
L'Unità, il manifesto, and Liberazione''. Her writings focused on issues such as workers' rights, feminism, and communism. In 1974, she was co-founder of the
Proletarian Unity Party for Communism. She served four terms in Italy's
Chamber of Deputies and twenty years in the
European Parliament. As a
member of the European Parliament, she served as chair of the Committee on Culture, Youth, Education and the Media and of the Committee on External Economic Relations. She served as editor of
Nuova Generazione, a Communist youth magazine, and of
Liberazione, and also played an important role at
il manifesto. == Personal life ==