Robathan was born in 1951 and educated at Merchant Taylors' School, Northwood, and Oriel College, Oxford.
He served in the Coldstream Guards from 1974 to 1989 before leaving to pursue a career in politics. He served throughout the world and attended the Army Staff College, Camberley. He commanded an SAS troop for two years.
Robathan volunteered to rejoin the army, January - April 1991, and served as Chief of Staff of the Prisoner of War Guard Force in Saudi Arabia, Iraq and Kuwait.
Robathan was a councillor in the London Borough of Hammersmith and Fulham from 1990 to 1992.
He was MP for Blaby 1992-2010 and became MP for South Leicestershire in the May 2010 general election.
Robathan has served as PPS to Iain Sproat as Minister of State, Department of National Heritage 1995-97; Shadow Minister for: Trade and Industry 2002-03, International Development 2003, Defence 2004-05; Opposition Deputy Chief Whip 2005-10; Ministry of Defence: Parliamentary Under-Secretary of State (Defence Personnel, Welfare and Veterans) 2010-12, Minister of State for the Armed Forces from 2012.
He left the government in July 2014 and stood down in the 2015 general election.
In February 2016, Robathan was appointed as a member of the Trade Union Political Funds and Political Party Funding Select Committee. 
- Lord Robathan profile, parliament.uk, accessed 9 February 2016
- Accessed 21 march 2018
- Minister of State for the Armed Forces, Ministry of Defence, accessed 15 October 2012.
- EX-SAS man gets MoD job, The Sun, 15 May 2010.
- Rt Hon Andrew Robathan, parliament.uk, accessed 15 October 2012.
- Ministerial appointments: 7 October 2013, Prime Minister's Office, 7 October 2013.
- Reshuffle at-a-glance: In, out and moved about, BBC News, 15 July 2014.
- Dods, 'Arrivals, moves, departures', Civil Service World, 2 February 2016, accessed 5 February 2016