Buchan was born in Bulawayo, the son of white Rhodesian immigrants from Scotland. He farmed maize and cattle in Zambia until moving to Greytown in kwaZulu-Natal in 1976 to farm. His wife Jill explained the decision to leave Zambia in a 2009 video, saying "We always agreed that when we had children we’d bring them up ourselves and not send them away. That’s actually why we left Zambia, we didn’t want to put them on a plane and send them far from home."
In 1980 Buchan started Shalom Ministries to preach in his local community. Over time he became a full-time evangelist, handing over the day-to-day running of his farm business to his sons.
In 1998 Buchan wrote a book about his life, Faith Like Potatoes, the book was turned into a film of the same title in 2006. Angus Buchan's Ordinary People is a 2012 semi-biographical film that tells the story of the growth of Buchan's ministry from the 1970s to the present, and that of three fictional characters whose lives are changed after attending one of his conferences.
In 1980 Angus and Jill started Shalom Ministries. The main purpose of the ministry is to go out and preach in South Africa and Africa.
Beth-Hatlaim (House of the Lambs), is a children's home for 25 orphaned and abandoned children, founded in 1995.
Halalisani Farm School is a Christian farm school also administered by Shalom Ministries with approximately 200 pupils.
The Mighty Men Conference, organised by Shalom Trust, is a gathering of Christian men and boys, camping for a few days annually in the open. The sole purpose of the meeting is to mutually worship and connect with God, thus growing spiritually while in the beautiful outdoors they believe He miraculously created. It began with only 40 people and grew exponentially by the 6th time it was held gathering more than 200,000 in 2009 and by its 7th and final conference the following year (2010) seated more than 400,000. Since the completion of the conferences, other believers have been inspired to hold similar events.
Angus presents a 30-minute religious show, Grassroots on ETV, Sundays at 6:30 to 7, and Thursdays from 5:00 to 5:30, mostly filmed from his own farm.
He is also a full-time evangelist going around South Africa and Africa drawing very large crowds. His audience tends to be disproportionately white and male, and some commentators suggest Buchan's popularity among middle-class white men may be a response to white South African males' fear of black leadership and diminishing white control and political and economic power.
He is known as "Uncle Angus", the name the Afrikaans speaking people use to address him.
Criticisms of Buchan include:Teachings that reinforce male relational power; presenting a "soft patriarchy" with men assuming leadership roles that demand submission and obedience from women.
A reliance on the concept of prosperity theology (that faith will maintain or increase one's material wealth);
His followers are mostly white, but his teachings fail to address the key issue of political or economic reconciliation between black and white South Africans.
Buchan's unsubstantiated claims to have healed the sick at his services.
In 2010 Bruce Winship, a Durban businessman and a Trustee of Shalom Ministries was quoted as saying "Not one cent goes to Angus. He lives in the same wattle and daub house that he built on his farm. He drives the same old car. He doesn't even have medical aid." In 2014 Winship's relationship with Shalom Ministries came under press scrutiny when reports revealed that Winship's companies routinely withheld payments totalling thirty million rand from smaller construction contractors. In response, Buchan’s Shalom Trust established a twelve million rand fund to pay Winship's creditors.
Buchan's conservative views on topics such as homosexuality and female equality led to a local council in Scotland banning him from preaching in council-owned property in 2016. A representative of the Scottish Borders LGBT Equality Association said "“Buchan’s views that LGBTI people are diseased and can be cured, and that men should dominate women and physically punish children in the family unit are extremely damaging. In my view this crosses the line between freedom of speech and hate speech."Faith Like Potatoes: The Story of a Farmer Who Risked Everything for God. (ISBN 978-0825461118, 0825461111).
The Booth: Finding quiet time in the presence of God. (ISBN 978-1432103521, 9781432110062) by Angus Buchan.
The Seed Sower
Jesus ... a farmer ... and miracles
Is Jesus Enough?
Passing the Baton
A Farmer's Year
A Mustard Seed
Fathers and Sons
A People Saturated with God
Grassroots Volume 1
Come of Age - The Road to Spiritual Maturity, 2010, ISBN 978-0-85721-0210