Name the South African singer who is popularly known as the 'Songbird' of South Africa.

Miriam Makeba, known as 'Mama Africa', is indeed the famous South African singer referred to as the 'Songbird' of South Africa. She was a Grammy Award-winning artist and prominent anti-apartheid activist who used her music to advocate for human rights. Makeba was the first African artist to popularize African music globally.