Welcome to the Forum from the BBC World Service.
I'm Rajan Datta.
The Russian army stands at the gates of the capital of another country,
a country that Russia has previously occupied
and one that, according to Russian politicians, has no right to independent existence.
The situation looks bleak for the residents of the capital and the rest of the world expects it to fall soon.
But then, guided by a charismatic leader, the defenders of that capital city fight back.
And before long, they drive the Russian invaders back to where they came from.
Well, that capital city was Warsaw in Poland, not Kyiv in Ukraine.
And the year was 1920, not 2022.
But what happened in Poland just after the end of the First World War
not only bears strong similarities to what's going on in Ukraine right now,
but it also had a big impact on the future shape of interwar.
Russia, which by 1918 was governed by the Bolsheviks, wanted to reoccupy Poland and indeed Ukraine,
Belarus and some other countries too,
so that they could serve as a bridge for exporting Communist revolution to Western Europe.
The Poles, although outnumbered and outgunned by the Russians, resisted.
The result was the Polish Bolshevik War, which wasn't fully resolved until 1921.
To guide us through this significant historical conflict,
I'm joined by three distinguished historians.