Despite having only recently gained independence for the first time since the eighteenth century, Poland's nationalist president, Pilsudski, refused to accept the Curzon Line as its eastern border, and demanded instead the restoration of the eastern lands that were lost after the first Polish partition of 1772. Taking advantage of the chaos of the Russian Civil War, Polish troops moved eastwards, deep into Ukrainian territory. The Red Army's response was vigorous, however, and Pilsudski was thrown back to the outskirts of Warsaw. The Polish army regrouped and, with the help of Weygand, Pilsudski achieved the ‘miracle of the Vistula’ and again advanced deep into Russian territory. In the Peace of Riga (18 March 1921), Poland gained a new eastern border around 200 km (120 miles) to the east of the Curzon Line.
Subjects: Military History.