The House of Demidov also Demidoff and Dimidov, was a prominent Russian noble family during the 18th and 19th centuries. Originating in the city of Tula in the 17th century, the Demidovs found success through metal products, and were entered into the European nobility by Peter the Great. Their descendants became among the most influential merchants and earliest industrialists in the Russian Empire, and at their peak were predicted to be the second-richest family in Russia, behind only the Russian Imperial Family whose net worth was around $300 billion. The Demidov family scattered to America, Italy, and other European countries as a result of the February Revolution of 1917.

Count Pavel Pavlovich Demidov, 2nd Prince of San Donato was a Russian industrialist, jurist, philanthropist and nobleman of the House of Demidov. He was the only child of Finnish philanthropist Aurora Karamzin and Prince Pavel Nikolaievich Demidov.