[citation needed] Prior to his death in 1754, his father was a Captain-adjutant of Count Burkhard Christoph von Münnich.

For his contributions during the battles at the Prut River and the taking of Focşani he was awarded the Order of St. Vladimir, 4th class, with ribbon.

Later he distinguished himself at Izmail and was praised by Suvorov as one of those most contributed by his courage and discretion to gaining the complete victory over the enemy.

When Napoleon invaded Russia, Osten-Sacken returned to military service at the head of a reserve corps, based in Volynia.

During the remaining part of the Napoleonic Wars he participated in the campaigns of the Silesian Army under command of Blücher and was present at the Battle of Katzbach.

At the close of the war, Osten-Sacken commanded the 3rd infantry corps until the death of Barclay de Tolly, whereupon he succeeded him as the commander-in-chief of the 1st army.

On 22 August 1826 Count Osten-Sacken was promoted Field Marshal of the Russian Empire and on 22 September he received the Order of St. Vladimir of 1st degree.

In 1835 the 1st army was disbanded, while Osten-Sacken was dismissed from the military service with the reservation of the rank of commander-in-chief and with the right of residence at one of the imperial palaces.