Russia has marked Unity Day each November 4 since 2005, following a 2004 law signed by then-president Vladimir Putin. The holiday commemorates the expulsion of Polish-Lithuanian occupiers from Moscow.
"The volunteer corps was led by Dmitry Pozharsky and Kuzma Minin - these were true patriots, and their manliness, ability to rally the people, and loyalty to the fatherland defined the destiny of our country as an independent, self-reliant, and strong state," Medvedev told guests at the Kremlin, including leaders of non-governmental and cultural organizations, scientists, and prominent Russians living abroad.
The president said Unity Day has added significance amid difficult times for the country.
"This year was not an easy one for Russia. In a time of trials - military, political, and economic - we felt your support, your true love for Russia, for the people who live and work here."
The ruling United Russia Party has organized various public celebrations to be held throughout the country, marking Unity Day.
Unity Day effectively replaces celebrations of the Bolshevik Revolution, which had been held on November 7. Celebrations were moved forward by three days to avoid associations with the revolution.