Chona was born Sikaye Chingula Namukamba on 21 January 1930 at Nampeyo, near Monze in the Southern Province of the British colony of Northern Rhodesia.
His father was Hameja Chilala also known as Chief Chona whose mother, Nhandu Chinyama, was one of his father’s five wives.
Chona received his primary education at Chona out-school in Nampeyo established by the Jesuit mission at his father’s request and at Chikuni.
Mainza completed his secondary education at Mali Secondary School in Lusaka in 1951 and then worked as an interpreter at the High Court in Livingstone. However, his ambition was to become a lawyer.
In pursuit of his goal, Chona secured a scholarship that took him to London in 1955, where he studied at Gray’s Inn. He was called to the bar in 1958. While in England, he met other African nationalists, including Harry Nkumbula and Kenneth Kaunda whereby he also made contact with London-based White supporters of the nationalist cause, such as Simon Zukas and Doris Lessing.
Chona returned to Northern Rhodesia in December 1958, during his absence from Northern Rhodesia, politics had moved forward on several fronts.
He became the first president of the United National Independence Party (UNIP), the successor to ZANC.
Mwainza was elected deputy president of UNIP, but he had to leave Northern Rhodesia to avoid a charge of sedition brought by the increasingly rattled CAF authorities. He remained in London as UNIP’s overseas representative for more than a year. He also served as a UNIP delegate to the Federal Review Conference in London in December 1960 and returned home in February 1961.
In June 1961, Chona was elected National Secretary of UNIP and he remained in that post for eight years whereby he was instrumental in securing the short-lived coalition between UNIP and the ANC in January 1963.
Mainza Chona died on 11 December 2001, He was buried on 16 December in Monze, Zambia.