Zachariah Keodirelang Matthews was born  20th October, in 1901 Kimberley , the son of Peter Motsielwa and Martha Mooketsi Matthews, a Tswana mineworker who later opened a café. Though exposed to politics at a young age - his father was a Cape voter and his cousin, Sol Plaatje, a founder member of the ANC - Matthews devoted the first part of his life exclusively to education. From Lovedale, where Tshekedi Khama was his fellow student, he entered Fort Hare University and in 1923 became the first African to obtain a B A at a South African institution. In 1925 he was appointed first African head of Adams College in Natal, where Albert Luthuli was his colleague on the staff and his students included Anton Lembede and Jordan Ngubane. With Luthuli he attended meetings of the Durban Joint Council and held office in the Natal teacher's association, of which he eventually became president.

Bridging the gap between the old guard and the more militant younger members of the African National Congress in the late 1940s and 1950s, Zachariah Keodirelang Matthews exercised a major guiding and moderating influence on African political history in its most crucial period. He was at the same time South Africa's, and perhaps the continent's, most distinguished African intellectual.

In 1928 he married Frieda Bokwe, daughter of John Knox Bokwe. After private study, Matthews became the first African to earn an LLB degree in South Africa in 1930 and was admitted as an attorney to the Johannesburg Bar and the Transvaal division of the Supreme Court. However, he did not join the bar in order to continue his studies abroad. In 1933 he was invited to study Race Relations and Culture Contact with C. Loram at Yale University in the United States, and the following year he completed an MA there. He then went on to spend a year at the London School of Economics to study anthropology under Bronislaw Malinowski.

He returned to South Africa in 1935, and in 1936 was appointed lecturer at Fort Hare University in Social Anthropology and Native Law and Administration. It was during this year that he became member of the Royal Commission of Inquiry into Higher Education for Blacks in British East African and Anglo-Egyptian Sudan. After D. D. T. Jabavu's retirement in 1944 Matthews became head of Fort Hare's department of African Studies and was promoted to the post of professor.

From 1936 to 1939 he was a research fellow of the International Institute of African Languages and Cultures, and during his long career in public life he served in the following bodies, among others: the Ciskeian Missionary Council, the Royal Commission on Higher Education for Africans in British East Africa and the Anglo-Egyptian Sudan, the Federation of African Teachers' Associations, the Union Advisory Board on Native education, the executive committee of the South African Institute of Race Relations, and from 1942 to 1950, the Natives' Representative Council (NRC).

Though he joined Jabavu in launching the All African Convention in 1935 to 1936, Matthews found his true political home in the ANC. Once the threat of the Hertzog Bills had aroused his sense of duty, he became increasingly immersed in political activities, and his talent and prestige elevated him immediately to the role of major spokesman for African interests. While considered cautious and conservative by some of his more radically inclined students, he never succumbed to the temptation to become a government-supported 'leader' on the Booker T Washington model, broad as the scope for this type of leader might have been at the time Matthews entered politics. Instead he used his position on the NRC to argue the African cause with consistency and force, chaired the committee that drew up African Claims, and lent his active support to the writing of the ANC's 1949 Programme of Action. Though criticized by the Youth League for waiting too long to resign from the NRC, Matthews - unlike some leaders - never got the reputation of being a political position - seeker: He had in fact the opposite inclination. In spite of his ambivalence on the boycott issue the Youth League "king-makers" were nearly unanimous in considering him the best candidate for ANC president-general in 1949.

Matthews, who in June 1949 had succeeded James Calata as ANC provincial president for the Cape, declined the league's invitation to be a candidate, however. In June 1952 he left South Africa on the eve of the Defiance Campaign and took up a position as visiting professor at New York's Union Theological Seminary. He returned home in May 1953, after the collapse of the campaign.

Believing that a dramatic new initiative was needed from Africans, Matthews proposed the basic idea of the Congress of the People in his presidential address to the Cape annual conference in August 1953. Because of his position and international reputation, he was spared from the bans and restrictions that hindered so many of his political colleagues, including his own son Joe Matthews. He was not spared, however, in the arrests of December 1956, when he went from being acting principal of Fort Hare to being an accused in the Treason Trial.

On his release from the trial in late 1958, he returned to Fort Hare, but subsequently resigned his post, forfeiting a large sum in pension benefits, in protest against the government takeover of the college. After being released from six months' detention during the 1960 emergency, Matthews joined Luthuli in calling for consultations among African leaders and a national convention representing all South Africans. These efforts eventually led to the All-In African Conference of March 1961. The same year Matthews moved to Geneva to become secretary of the Africa division of the World Council of Churches.

In 1965 he notified President Sir Seretse Khama that he would retire to Botswana, which had just attained self-government status. In 1966, Botswana gained independence and Matthews was offered the post of ambassador of Botswana to the United States, which he accepted. Matthews died in 1968 in Washington, United States and he was buried in Gaborone, Botswana. 

A sample of his writings:

"A New Native Teachers' Course", Ilanga lase Natal , November 4, 11, 1927

"Bantu Law and Western Civilisation in South Africa: A Study in the Clash of Cultures , Yale University, 1934. Master of Arts thesis."

“A Short History of the Tshidi Barolong", Fort Hare Papers , vol. 1 no. 1, June 1945

"Foreword", in Responsible Government in a Revolutionary Age, [ed.] Z. K. Matthews, Association Press, New York, 1966.

"Freedom For My People", Cape Town: Collings, 1981. (Published posthumously in 1981)

"Africa holds her own". An appreciation of Bantu tribal and national culture in the Imperial Protectorates and in the Union of South Africa. By W. Bryant Mumford. in co-operation with Hugh Ashton . [and] Z.K. Matthews.

"African awakening and the universities", [Cape Town] University of Cape Town, 1961.

"Africa Today and Tomorrow", New York : Union Theological Seminary, [19--].

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