He went on to be British Commissioner with the Turkish Army providing advice to General Omar Pasha during the Crimean War.[2] Returning to the United Kingdom in 1845, Simmons became an instructor at the Royal Military Academy, Woolwich with promotion to second captain on 9 November 1846.The British Ambassador, Lord Stratford de Redcliffe, took up Simmons' offer of his services, requesting that he report on Turkish defences and their ability to resist a Russian advance.[2] Promoted to captain on 17 February 1854,[5] he became British Commissioner with the Turkish Army providing advice to General Omar Pasha as the Crimean War started.[16] After he retired in September 1888,[17] the Foreign Office continued to utilise his services and in 1889 he went to Rome as Envoy Extraordinary and Minister Plenipotentiary to Pope Leo XIII.
The Battle of Eupatoria, at which Simmonds served with the Turks, during the Crimean War