Teesdale was 22 years old, and a lieutenant in the Royal Regiment of Artillery, British Army during the Crimean War when the following deed took place for which he was awarded the VC.
On 29 September 1855 at Kars, Turkey, Lieutenant Teesdale volunteered to take command of the force engaged in the defence of the most advanced part of the works.
During the hottest part of the action he induced the Turkish artillerymen to return to their post from which they had been driven by enemy fire and after the final victorious charge he saved from the fury of the Turks a considerable number of the enemy wounded – an action gratefully acknowledged by the Russian Staff.
He was decorated with the VC by Queen Victoria in the quadrangle of Windsor Castle on 21 November 1857 along with James Craig, George Symons and Joseph Malone.
He was appointed as Master of The Ceremonies and Extra Equerry to The Prince of Wales on 9 November 1858, positions he held until his death and was also made aide-de-camp to Queen Victoria on 1 October 1877.