With the accession of Emperor Alexander I in 1801, Korsakov was re-appointed as a GvC cavalry general. He was Governor of Lithuania from 1806 to 1809, based at Vilna, and again from April to June, 1812. On the approach of the French he was ordered to withdraw by Barclay de Tolly on 28 June, but returned to serve for a third term as Governor-General of Lithuania from 8 December 1812 until 1830. During this time he ordered the reconstruction of the Tuskulėnai Manor in Vilnius, where he lived. Recalled to St. Petersberg after the Polish insurrection of 1830–31, Korsakov was made member of the State Council of Imperial Russia. He died in 1840.