Tadasshi (Tad) Mitsui was born in 1932 in Japan and grew up in Tokyo and came to Canada after receiving Bachelor of Arts and of Divinity (BA and BD) from Tokyo Union Theological Seminary. He came to Canada in 1957, qualified to be an ordained minister of the United Church of Canada with Master of Sacred Theology (STM) from the Union College affiliated with the University of British Columbia, and later Doctor of Sacred Theology (STD) from the United College affiliated with McGill University. He was the minister of Vancouver Japanese United Church. In 1968 he took up a position as Lecturer of the University of Botswana, Lesotho, and Swaziland and taught for eight years with Desmond Tutu as a colleague and involved heavily in Anti-Apartheid movement, detained briefly before being expelled from South Africa. He lived in Geneva, Switzerland for six years, worked in World University Service and World Council of Churches and continued working for Africa. Back in Canada he lived in Toronto and Montreal and worked for the church administration until retired in the year 2000.