It lasted from June 1920 until September 1921 and was established by Mirza Kuchik Khan, a leader of the "Constitutionalist Movement of Gilan", and his Jangali partisans, with the assistance of the Soviet Russia's Red Army.

The new administration, formally under Ehsanollah Khan but actually under the influence of Batyrbek Abukov (the Soviet Commissar) started a series of radical activities such as anti-religious propaganda, or forcing money out of the rich landlords.

The Republic also lost support from the general population due to the exceedingly high number of war refugees who began flooding the urban centers, thus posing a significant economic problem.

Reza Khan Mirpanj, who had initiated a successful coup d'état with Seyyed Zia'eddin Tabatabaee several days beforehand, then began reasserting central government control over Gilan and Mazandaran.

Some of the main studies including those by Gregor Yeghikian and Ebrahim Fakhrayi (Minister of Culture in Kuchak Khan's Cabinet of the Soviet Republic) suggest a role for both extremist actions taken by the Communist (Edalat) Party that provoked opposing religious sentiment among the public, and Mirza Kuchak Khan's religious and at times somewhat conservative views on collaboration with the Communist Party as possible factors.

[9] As part of his peace making efforts, Rothstein had also sent a message to the Soviet officers among Ehsanollah Khan's one thousand strong force that had made its way towards Qazvin, not to obey his orders and as a result that campaign was defeated.

Historian Kayhan A. Nejad counters that Soviet leaders in Moscow only began to withdraw support from the Gilan Republic after months of infighting between its communist and non-communist factions, which set into motion a process of internal collapse.