M.C. London Gazette 22.9.1916 'For conspicuous gallantry in action. When he reached the enemy first line, he found that the men carrying guns had become casualties. He returned through a heavy barrage, re-organised his men and led them on again to the attack'.

Lieutenant-Colonel Basil Joseph Corballis, M.C., was mobilised from the Special Reserve on the outbreak of hostilities and fought with the 1st Battalion, Somerset Light Infantry in France and Belgium between September 1914 and January 1915, a period of service that would have encompassed several bloody engagements in the vicinity of Ploegsteert Wood. Returning to the Western Front in the Summer of 1915, he transferred to the Machine Gun Corps at the end of the year and, according to one Regimental History, won his M.C. for the First Day of the Somme. Corballis was advanced to Temporary Lieutenant in November 1916 and invested with his Decoration in the following month. Remaining on active service in France until late July 1918, he was further advanced to Acting Captain in July 1917 and to Acting Major in March 1918, his attachment to the Machine Gun Corps extending to March 1921 and encompassing the operations in Iraq. Afterwards returning to the Somerset Light Infantry, Corballis attained the rank of Major in November 1937 and Lieutenant-Colonel in January 1944, shortly before his participation in operations in North West Europe. Foreign Office files verify his entitlement to the Legion of Honour for the 1939-45 period.