was born in England in 1946, the son of the County Tipperary-born historian Nicholas Mansergh. Martin Mansergh was educated in England at The King's School, Canterbury and Christ Church, Oxford. Mansergh studied Philosophy, Politics and Economics in Oxford, and obtained a Doctorate in French history. He entered the Department of Foreign Affairs by open civil service competition in 1974, and was promoted to the position of First Secretary in 1977. Later recruited by Taoiseach Charles J Haughey, he has worked for the Fianna Fail party ever since, serving under three Fianna Fail leaders as Director of Research, Policy and Special Advisor on Northern Ireland where he was involved in discussions between the nationalist parties and the Irish Government and met regularly with intermediary Father Alec Reid.