Alexander Samoylov was born into the family of senator Nikolay Samoylov. He started his military service in 1760 as a soldier of Leib-Guard Semyonovsky Regiment. Later he was moved to the front-line forces and took part in the Russo-Turkish War, 1768–1774 and, for his part in the taking of Silistra, received the Order of St. George of 4th degree. Alexander Samoilov married Princess Troubetzkoy and had one son, Nicholas, who did not leave issue from his marriage to the last Countess Skavronsky, Yulia. General Raevsky was his nephew.