Michael Williams was born on 11th Jun 1949 in Bridgend, Glamorgan. He was educated at Sandfields Comprehensive School in Port Talbot, and from there won a place at University College, London, where he earned a BSc in International Relations in 1971. He then attended the School of Oriental and African Studies, gaining an MSc in politics in 1973 and a PhD in 1984. He worked as a researcher at Amnesty International from 1977-1978 and as a lecturer in politics at the University of East Anglia from 1978-80, before returning to Amnesty International as head of the Asia Research Department from 1980-1984.

In 1984 Williams moved to the East Asia section of the BBC World Service. In 1992 he joined the United Nations as Deputy Director of Human Rights in the UN Transitional Administration in Cambodia (UNTAC). In 1993 the head of the mission, Yasushi Akashi, moved on to a new assignment as UN Representative in the former Yugoslavia, and took Williams with him as Director of Information. Williams later gave evidence against the Serbian president Slobodan Milosevic during the latter’s trial for genocide at the International Criminal Tribunal for the former Yugoslavia in The Hague.

From 1996 to 1998 Williams was a senior fellow at the International Institute for Strategic Studies in London. He then returned to the United Nations in 1998 as Chief of Staff to the Special Representative of the Secretary-General for Children and Armed Conflict in New York. After this, he returned to London and became political adviser to Foreign Secretary Robin Cook, and after the 2001 election to Cook's successor Jack Straw. In this post he acquired a detailed knowledge of the Middle East, and in 2005 returned to the UN as Director for the Middle East and Asia in the Department of Political Affairs. In 2006 he was promoted to a new post of Special Adviser on the Middle East, with the rank of Assistant Secretary-General. In 2007-2008 Williams returned to London and worked with Foreign Secretary David Miliband, as Special Representative for the Middle East and Special Projects. In October 2008 he went to Beirut as United Nations Special Co-ordinator for Lebanon, with the rank of Under-Secretary-General.

In the 2010 dissolution honours list, Gordon Brown appointed Williams to the House of Lords. On his return from Lebanon in October 2011, he became a member of the BBC Trust and sat as a crossbencher. He also became a distinguished fellow at Chatham House.

On 8th May 1974 Williams married Margaret Esmee Veronica Rigby. They had a daughter, Rhiannon, but divorced in 1984. Williams remarried to Isobelle Mary Jaques in 1992, and they had one son, Ben.

Williams died at home of pancreatic cancer, on the 23rd April 2017. At the time of his death he was chair of the trustees of the de-mining charity, Mines Advisory Group, a governor of the School of Oriental and African Studies, and a member of the council of Swansea University.