According to the Wikipedia page (lol):
Treaty on the Creation of the USSR
On 28 December 1922, a conference of plenipotentiary delegations from the Russian SFSR, the Transcaucasian SFSR, the Ukrainian SSR and the Byelorussian SSR approved the Treaty on the Creation of the USSR[27] and the Declaration of the Creation of the USSR, forming the Union of Soviet Socialist Republics.[28] These two documents were confirmed by the first Congress of Soviets of the USSR and signed by the heads of the delegations,[29] Mikhail Kalinin, Mikhail Tskhakaya, Mikhail Frunze, Grigory Petrovsky, and Alexander Chervyakov,[30] on 30 December 1922.
https://twitter.com/zei_squirrel/status/1609002520411619329
Happy Anniversary to one of the biggest attempts at a better world
don't be sad it's over, be happy it happened
actually you know what fuck it, be sad it's over
:rosa-salute: :sankara-salute: :maduro-salute: :deng-salute: :chavez-salute: :kim-salute: :fidel-salute: :lenin-laugh: :stalin-pipe:
:reddit-logo: r/europe post about this if full of nazis and double genocide bullshit because of course it is.