Born and raised in Mbewuleni, Cape Province, Union of South Africa, Mbeki is one of four children of Epainette and Govan Mbeki. The economist Moeletsi Mbeki is one of his brothers. His father was a stalwart of the African National Congress (ANC) and the South African Communist Party. He is a native Xhosa speaker.

In January 1975, just a few months after his marriage to Zanele, Mbeki was sent to Swaziland to assess the possibility of setting up an ANC frontline base in the country. Ostensibly attending a UN conference, Mbeki was accompanied by Max Sisulu. The duo met with Sisulu's sister, Lindiwe Sisulu, who was studying at the University at Swaziland. Lindiwe set up a meeting for the two at the home of S'bu Ndebele, then a librarian at the university. Mbeki and Sisulu held meetings in Swaziland for a week with South Africans studying there to assess the situation. They returned to Lusaka after a week, when their visas had expired. Mbeki reported back to the ANC that the possibility of establishing an ANC base in Swaziland was promising, especially because of its location, as it was close to Johannesburg and Durban. As a result, Mbeki was sent back to Swaziland to recruit soldiers for the organisation's military wing. In Swaziland, Mbeki recruited hundreds of people into the ANC. He also liaised with Buthelezi and the latter's newly formed Inkatha movement, and set up structures within South Africa. Mbeki's aim was to establish contact with as many Black Consciousness Movement (BCM) members as he could and to draw them into the ANC. Ironically, while Mbeki was converting BC adherents into ANC members, he would himself absorb many aspects of BC ideology.  In March 1976, Mbeki, Albert Dhlomo and Jacob Zuma were arrested in Swaziland, but the trio managed to escape deportation to South Africa. Instead, a month after their arrest, they were escorted across the border to Mozambique. From there, Mbeki went back to Lusaka for a few months before being posted to Nigeria in January 1977. Before leaving Lusaka, Mbeki was appointed as deputy to Duma Nokwe in the Department of Information and Propaganda (DIP). Mbeki's mission in Nigeria was to establish diplomatic relations with Olusegun Obasanjo's regime, - a mission that proved to be quite successful as Mbeki was to build a lasting relationship with the Nigerian authorities, eclipsing the Pan Africanist Congress (PAC) in Nigeria. Zanele, who was running the Africa offices of the International University Education Fund in Lusaka, spent much of 1977 with her husband in Nigeria.  In 1978, Mbeki became political secretary in the office of Oliver Tambo. He became a close confidant of Tambo, advising him on all matters and writing many of his speeches. One of his duties as secretary was to choose a theme each year in accordance with the ANC's current activities - 1979, for example, was known as "The Year of the Spear", while 1980 was "The Year of the Charter." From 1979, with Mbeki as his right-hand man, Tambo began building up the guerrilla movement into an internationally recognised guardian of South African freedom.

Using a quote from the above article, answer the following question: what else was he responsible for?
In 1978, Mbeki became political secretary in the office of Oliver Tambo.