There were a number of reasons behind the move

1. The foreign threat: the proximity of Petrograd to German, Finnish, or Baltic areas was too much of a security risk especially given the parlous state of the Russian Army. The German occupation of Pskov in February 1918 following the breakdown of peace negotiations created the spectre that the Germans could occupy Petrograd and set up a pliant puppet regime.

2. Infrastructure: Petrograd was not a self-sustaining city in wartime conditions. It was hard to supply grain to the city and this created the urban unrest that sparked the February Revolution. The Bolsheviks were acutely aware of this fact. Additionally, the rail lines within Moscow and its factories were essential to maintain inner lines of communication during the Civil War.

3. Ideology: Moving to Moscow was congruent with a number of Bolshevik prerogatives. Unlike Petrograd, Moscow was the traditional industrial center of the tsarist state. Now there was an expansion of Petrograd's industrial area in the run up to the war and the war accelerated this process. But Moscow had the largest established working class population and thus would be a suitable capital for Bolshevik state.

4. Politics: Although the Bolsheviks had gained much political ground within Petrograd, the urban politics of the imperial capital were constantly shifting. While the Bolsheviks had success in cultivating the support of the Petrograd Soviets, they never had full control over them. Moscow's support for the Bolsheviks was much more stable and less conditional than in Petrograd.

Now none of these rationales were mutually-exclusive and they often reinforced each other in the hectic post-October Revolutionary days.