William Earle Molesworth was the son of Colonel Molesworth, C.I.E., C.B.E., of the Indian Army Medical Service. He attended Marlborough College in Wiltshire, England from 1908 to 1912 followed by four years at the Royal Military College at Sandhurst from 1912 to 1914. Receiving a regular commission as a 2nd Lieutenant in the Royal Munster Fusiliers on 8 August 1914, Molesworth served on the Western Front from October 1914 to March 1916, being wounded in December 1914. In March 1916, he received a temporary commission in the Royal Flying Corps and completed his training at the Central Flying School at Upavon in February 1917. He was then posted to 60 Squadron in France where he served under Captain Albert Ball. Promoted to flight commander in April 1917, Molesworth assumed command of A Flight. Flying the Nieuport 17 and the S.E.5a, he flamed one balloon and scored five victories during several fights with Manfred von Richthofen's Flying Circus. Returning to the England in August, Molesworth was ordered to Dover where he assumed command of a training flight before being reassigned to the Gosport Special School for Advanced Flying. On 20 October 1917, he returned to France, this time joining 29 Squadron under Captain James McCudden. Flying Nieuports again, Molesworth scored twelve more victories. On 17 March 1918, he was posted back to the Home Establishment where he served as an instructor at the Central Flying School. In April, with the creation of the Royal Air Force, Molesworth became responsible for the formation of 158 Squadron at Upper Heyford, Oxfordshire. He served as this squadron's first commanding officer until October 1918. In November 1918, following the signing of the Armistice, Molesworth transferred back to the Royal Munster Fusiliers.
Several of William Molesworth's letters home from the war were published in Flypast magazine during 1979 and 1980.
Military Cross (MC)
Capt. William Earle Molesworth, R. Muns. Fus. and R.F.C.
For conspicuous gallantry and devotion to duty on offensive patrol. He has frequently led his patrol against superior numbers of the enemy, destroying some and dispersing others. He has also brought down two balloons and has proved himself to be a dashing and fearless pilot of great skill and determination.
Supplement to the London Gazette, 9 January 1918 (30466/631)
Military Cross (MC) Bar
Capt. William Earle Molesworth, M.C., R. Muns. Fus. and R.F.C.
For conspicuous gallantry and devotion to duty. He has done excellent work as patrol leader, handling his formations with great skill and courage. He has destroyed four enemy machines and driven several down out of control.
Supplement to the London Gazette, 24 August 1918 (30862/9904)