Nyasulu was born in Mzimba District, Nyasaland, on 23 February 1920, although the Historical Dictionary of Malawi listed his birthplace as Rumphi.

[1][2] After receiving an education at local schools, he later studied to become a teacher at the Overtoun Institute, run by a Presbyterian mission in Livingstonia.

[3] Nyasulu joined the Army during World War II and served in India, Ceylon, and across East and Central Africa.

[3] Afterwards, Nyasulu worked as a teacher for local schools before attending the Institute of Education, University of London, where he was one of the first students from Nyasaland.

[5] Nyasulu later fell out of favor with President Hastings Banda, who dismissed him as speaker in February 1975,[5] suspended him from the MCP, and then imprisoned him without trial.