The October Revolution Day commemorating the Bolshevik uprising in Petrograd – currently St Petersburg – on 25 October in 1917, was celebrated on 7 November, according to the calendar introduced by the Bolsheviks.
In Soviet times it was the main public holiday. Its celebration involved massive military parades and demonstrations watched by Soviet leaders lined up on Lenin’s mausoleum in Red Square.
Source: BBC News
As communism fell in Russia so to did the popularity of the holiday. It was redubbed “National Reconciliation Day” but even with the slightly “friendlier” naming it still was only celebrated by the hardest communist sympathetics.
In December of 2004 the government removed the holiday entirely, instead electing to replace it with “People’s Unity Day”, which would be celebrated on November 4th instead.