Field Marshal William Edmund Ironside, 1st Baron Ironside (b. Edinburgh, 6th May, 1880; d. London, 22nd September, 1959) was the second child of Surgeon-Major William Ironside, and was educated at Tonbridge School. He was a British military figure, who served as Chief of the Imperial General Staff during World War II, but is noted for his important role as commander of British forces in Persia in 1920-1921.

Ironside joined the British Army as a field artilleryman. In 1902 Ironside was sent to South Africa and during the Boer War worked as a spy. These experiences later resulted in him being used as the model for Richard Hannay, the character that appeared in the novels of John Buchan.

In 1908 Ironside was promoted to captain and on the outbreak of the First World War was sent to France and served on the Western Front. He fought at Vimy Ridge and Passchendaele and in 1918 reaching the rank of colonel, was put in charge of the Machine Gun Corps.

Ironside was sent to Archangel in north Russia in 1918, and placed in command of the Allied army fighting against the Bolsheviks. The Red Army managed to eventually gain a superior position in the Civil War and in autumn, 1919 he was forced the abandon the White Army to their fate.

In 1920 Ironside served with the British forces in Izmit, Turkey. He commanded some 6000 British forces in Persia (NORPERFORCE ) with headquarters in Qazvin from 4 October 1920 to 18 February 1921. Ironside's four and a half months in Persia were known primarily for two accounts. First, his role in the discharge of more than a hundred Russian officers and NCOs of the Cossack Division and their replacement by Persians under the command of Reza Khan, founder of the Pahlavi dynasty; and second, his encouragement of Reza Khan's coup d'e‚tat of 1921. On each occasion Ironside acted on his own responsibility without authority from London. He distrusted Russian loyalties after the 1917 Revolution and with the assistance of Herman Norman , the British Minister in Tehran, persuaded a Shah to dismiss the Cossack Division's commanding officer, and every Russian under him. It was also Ironside who selected Lt. Colonel Reza Khan as the Russian's successor. The appointment was based on the advice of a British officer friend, attached to the Cossacks for a short time, and after several visits to their camp near Qazvin where he was much impressed by the Persian contingent. Ironside's decision "to let the Cossacks go" was, according to his diary, because he wanted a strong military commander in the capital to save the country from the Bolsheviks and chaos and safeguard the imminent withdrawal of NORPERFORCE from Persia. In return, Reza Khan promised not to hinder British withdrawal or depose the Shah.

In 1936 Ironside became a general and was appointed head of the Eastern Command and served as governor and commander in chief of Gibraltar (1938-39). Ironside became Chief of the Imperial General Staff in September 1939 when he replaced General John Gort who had been sent to France as head of the British Expeditionary Force at the outbreak of World War II. In May 1940, when a German invasion of Britain seemed imminent, Ironside was appointed Commander-in-Chief of Home Forces but was replacedin July that year. In 1941 he became Baron of Archangel and retired from active service. William Edmund Ironside died on 22nd September 1959.