Official records put the figure of deaths at the hand of the Cheka from 1918-20 at nearly 13,000.
Increasing opposition to the regime from workers who wanted Soviet elections, a free press, restoring the Constituent Assembly and overthrowing the Sovnarkom led to more clashes with the Cheka.
Graffiti appeared in Petrograd saying "Down with Lenin and horsemeat, give us the Tsar and pork!"
A campaign was launched by some left-wing SRs who were protesting about the Treaty of Brest-Litovsk.
They captured Dzerzhinsky, Head of the Cheka in May 1918.
In July 1918, the left SRs shot the German Ambassador and in August, there was an assassination attempt on Lenin who was shot in the neck and badly wounded.
There was an increase in support for the other socialist parties.
The SRs and Mensheviks both enjoyed a growth in support which was accompanied by calls for a return to multi-party democracy.
The Cheka fanned the flames of class warfare threatening to wipe out the middle class.
However, the main aim of the Terror was to frighten all social groups into cooperation with the regime.
Victims of the terror included large numbers of workers and peasants as well as princes, priests, prostitutes, judges, merchants/
Children made up 5% of Moscow's prison population in 1920.
They alongside other groups were found guilty of "bourgeois provocation" or "counter-revolutionary activities".
Apologists for Lenin argue that he was faced with enormous political and economic challenges during the Civil War and that the use of terror was a necessary response to the crisis.
"Lenin cannot be accused of personal cruelty. The main argument for the terror was to protect the working class." - D Volkogonov.
Once the crisis passed, the Cheka was disbanded by Lenin in February 1922.
Critics of Lenin do not accept that the Red Terror was temporary policy born out of desperate circumstances.
"The Red Terror constituted form the outset as an essential element of the regime. It never disappeared, hanging like a permanent cloud over Soviet Russia." - Richard Pipes
Lenin's critics also point out that despite the Cheka being disbanded in 1922, it was immediately replaced by the GPU who continued the work of the secret police.
Lenin's critics see the foundations of Stalin's purges in the 1930s coming from the Red Terror whereas apologists regard Stalin's later escalation of terror as something different.