Territorial disputes between Poland and Czechoslovakia 1938–1945

The historical point of view is important to fully understand foreign affairs. For Polish-Czech relations the crucial period in this respect is 1918–1945. The matter of the conflict were borderlands, with the most important one – Zaolzie, that is, historical lands of the Duchy of Cieszyn beyond Olza River. Originally, the land belonged to the Crown of the Polish Kingdom, then to the Kingdom of Bohemia and Austrian Habsburg dynasty. After World War I, local communities took control of the land. Czechoslovakian military intervention and a conflict with Bolsheviks caused both parties to agree to the division of Zaolzie through arbitration of powers in 28 July 1920. Until 1938, key parts of Zaolzie belonged to Czechoslovakia. In that year, Poland decided to annex territories lost according to the arbitration. After World War II tension between Poland and Czechoslovakia heightened again. Czechoslovakia made territorial claims on parts of Silesia belonging to Germany. Poland once more tried to reclaim Zaolzie, but military invasion was stopped by Stalin. Negotiations failed, but the escalation of the conflict was stopped. Two years later the relationship between the parties was eventually normalized, the final agreement was signed in 1958 and it is still in place today.