In 1629 he was a colonel in Sweden, sent by KingGustav II Adolfon a mission to Moscow and entered the Tsar's service. During the audience by king Michael I of Russia as a member of Swedish mission in Russia he gave a petition for military service in Russia in January 1630. Since March 1630 Colonel Leslie in Russian service. Leslie returned to Sweden in April 1631 to inform Gustav Adolf that war between Russia and Poland was imminent. In 1631 he recruited thousands of soldiers in western countries including Scotland and supervised the first regiments of "foreign order", that was the Russian term that was used to describe military units organised and armed along western lines. He subsequently advanced to the rank of a Russian General and was commander of Russian forces during the Siege of Smolensk, one of the first great events of the Russo-Polish War. Leslie went abroad after the unhappy outcome of the campaign of Smolensk War. Charles I of England wrote to Russian TsarMikhail Fyodorovich on behalf of Leslie in March 1637 saying that he was returning to Britain on private business. He writes:
Auchintoul fought for the Montrosians in the Civil War. He was captured at Philiphaugh and, by the direct intervention of Lieutenant GeneralDavid Leslie, was dealt with leniently compared to other prisoners. With David Leslie vouching for him directly, Auchintoul avoided execution. When David Leslie's petition was read, by Argyll among others, Auchintoul was spared, but was banished from Scotland for life.
Back in Russia from 1647
So sentenced, Auchintoul returned to Russia at some point after that, with a recommendation from King Charles I and finally settled in Muscovy in 1647. Converted to Ortodoxy in September 1652, his Gods father was PrinceIlya Miloslavsky, after that act he received 23 000 silver rubles. After capitulation of Mikhail Shein in Siege of Smolensk to Poles his regiment was the only that leave the battle with flags and arms.
Family
Alexander Leslie of Auchintoul, General and voivode of Smolensk had three sons, Colonel Alexander, Yakov-John and Colonel Fedor-Theodore, commander of :ru:Белгородский разряд|Belgorodski Regiment.
* John Leslie of Balquhain, son of General Alexander Leslie, was a Scottish cavalry colonel in Russian service killed in the storming of Igolwitz castle on 30 August 1655, he married a daughter of Colonel Crawford in Muscovy, though there are at least three Crawfords with that rank in the Russian service, so it's not entirely clear who is meant.