August 15 is considered the anniversary of the Polish victory in the Battle of Warsaw. The battle in which the Poles defeated Bolshevik Russia. This huge battle between Dęblin and the border with East Prussia was the sum of several clashes, the results of which were decided by the determination of the Polish command and soldiers, as well as a perfectly prepared action plan.
The Polish-Bolshevik war began shortly after Poland regained independence. The Red Army gradually occupied areas abandoned by German forces. At the end of December 1918, it clashed for the first time with Polish self-defence units in Vilnius. The aim of the Bolsheviks’ actions was not only to restore the borders of the Russian Empire from before March 1918 but above all to provide aid to the communists who, at the same time, were trying to start a revolution in Germany and in the countries that emerged from the collapse of Austria-Hungary. Moscow, therefore, sought to shift the fire of the revolution to the west. Reborn Poland stood in its way.
The Battle of Warsaw was fought following the operational plan developed by the Chief of General Staff, General Tadeusz Rozwadowski, Colonel Tadeusz Piskor and Capt. Bronisław Regulski.
The main focus of the fights for the foreground of the capital was Radzymin, which passed from hand to hand several times. In the end, Polish soldiers, despite losing the first line of fortifications and with great losses, kept Radzymin and other towns, throwing the enemy far away from their positions. Heavy battles were also fought at nearby Ossów. On August 14, Soviet troops found themselves 13 km from the borders of Warsaw.
The defensive phase of the Battle of Warsaw lasted until August 16. Commanded by Piłsudski, the so-called manoeuvring group, which included five infantry divisions and a cavalry brigade, broke through the very weak Bolshevik defences in the area of Kock and Cyców, and then attacked the rear of the Bolshevik troops attacking Warsaw. On August 18, after the clashes at Stanisławów, Łosice and Sławatycze, the Polish forces found themselves on the line Wyszków-Stanisławów-Drohiczyn-Siemiatycze-Janów Podlaski-Kodeń. Faced with the complete disintegration of his army, Tukhachevsky had to retreat to the Neman. The Battle of Warsaw was recognized as the eighteenth breakthrough battle in the history of the world.