Pavel Nikolaievich Demidov

Pavel (called Paul) Nikolaievich Demidov (; 6 September 1798 – 25 March 1840) was a Russian nobleman of the Demidov dynasty. 
Life.
The eldest son of Count Nikolai Nikitich Demidov and Baroness Elisabeta Alexandrovna Stroganova, he fought as an officer in his father's regiment and received his baptism of fire at the battle of Borodino in 1812. After the war he entered the Chevalier Guards regiment. In 1828 he purchased the Sancy diamond. He received his regimental discharge in 1831 with the rank of captain, at which time he entered civil service as governor of the province of Kursk. Also in 1831 he founded the Demidov Prize (decided by the Russian Academy of Sciences).
In 1834 he entered service in the Ministry of the Exterior as court Huntsmaster, later State Councillor. In Helsinki on 9 January 1836 he married the well-known society beauty and maid-of-honour to Her Majesty the Empress Alexandra Feodorovna, Baroness Aurora Stjernvall (1808–1902) - they had one son, Pavel Pavlovich Demidov, 2nd Prince of San Donato (1839–1885), whose daughter Aurora was mother of Prince Paul of Yugoslavia.