Renowned for their sword-fighting prowess and notorious for their anti-Semitism in tsarist Russia, the Cossacks are taking on new foes: beggars, drunks, and improperly parked cars.
The Kremlin has sought to use the once-feared paramilitary squads in its new drive to promote conservative values and lure nationalists.
Among the first were eight Cossacks clad in traditional fur hats and uniforms who patrolled a Moscow train station looking for signs of minor public disturbances.
The patrol, approved by the authorities, is a test-run on whether the group can become an armed and salaried auxiliary police force, like the Texas Rangers, with the power of arrest, patrol leader Igor Gurevich said.
The conservative Cossacks have increased their political activity in response to an impromptu protest that feminist punk rockers Pussy Riot staged in Moscow's main cathedral in February. Groups of Cossacks recently barred visitors from entering a Moscow art exhibition that daubed Pussy Riot's trademark balaclavas over Orthodox Christian icons, and they led a successful campaign to cancel a staging of Vladimir Nabokov's novel Lolita in St Petersburg.
A government-backed Cossack political party held its first congress in Moscow last weekend. Six other groups have applied to form splinter Cossack parties.
President Vladimir Putin was inducted into what is known as the Cossack host in 2005 and given the rank of Cossack colonel, previously held by imperial tsars.
Russia plans to restore the functions Cossacks had in the imperial Russian army, where they were instrumental in repelling Napoleon's invading army in 1812 and led pogroms against Jews. A 400,000-strong All-Russia Cossack Host directly subordinate to Putin is scheduled to be launched by the end of the year.