 He was promoted to the rank of lieutenant-general in 1807.On 22 February 1799 Lieven received the title of Count, as his mother was granted a countship.Somewhat overshadowed by his more illustrious wife, the famous socialite and political force, Dorothea Lieven, née Countess von Benckendorff (17 December 1785, Riga – 27 January 1857, Paris), whom he had married on February 1, 1800 in St. Petersburg.