88th Anniversary of the Miracle on the Vistula
From Wikipedia: Battle of Warsaw (1920)
The Battle of Warsaw (Russian: ВаршáвÑкое Ñражéние, Polish: Bitwa Warszawska; sometimes referred to as the Miracle at the Vistula, Polish: Cud nad Wisłą) was the decisive battle of the Polish-Soviet War, which began soon after the end of World War I in 1918 and lasting until the Treaty of Riga (1921).
Before the Polish victory at the Vistula, both the Bolsheviks and the majority of foreign experts considered Poland to be on the verge of defeat. The stunning, unexpected Polish victory crippled the Bolshevik forces. In the following months, several more Polish victories secured Poland’s independence and eastern borders.

August 15th was the turning point. Polish forces at Warsaw routed the Russian army. It is said that an apparition of the Blessed Virgin Mary above the Wisła was the inspiration for the victory by the Polish forces.
Can you tell me who the artist is for this picture? I must get a replica. Thank you.
Unfortunately I do not know. The work is a propaganda poster used at the time of the Polish-Soviet War.