General Sir Mike Jackson has died aged 80, the British Army said.
Sir Mike, a former chief of the general staff and head of the Army, died on Tuesday surrounded by his family.
The father-of-three led the Army during the allied invasion of Iraq in 2003 after serving in Northern Ireland and Bosnia.
The British Army said in a tribute: “It is with great sadness that we have learnt of the death of General Sir Mike Jackson GCB, CBE, DSO, on October 15 surrounded by his family.
“General ‘Jacko’ served with distinction for over 40 years, finishing his career as chief of the general staff.
“He will be greatly missed, and long remembered. Utrinque Paratus.”
The Parachute Regimental Association said he was a “great leader of men” who will be “missed by many”.