In 1781 Frederick resigned from the Prussian Army as a major general and the following year he accompanied Sophie and her husband to Russia, after a Grand Tour of Europe that the imperial couple had undertaken. Pleased with the well-spoken and confident young man, Catherine II appointed Frederick Governor-General of Eastern Finland, with his seat at Viipuri. From June to October 1783 he was also in command of a 15000-20000 strong corps in Kherson during the Russo-Turkish War, but he was not significantly involved in combat.