Poland between the wars was an aggressive attacker. https://en.wikipedia.org/wiki/Polish–Soviet_War – https://en.wikipedia.org/wiki/Polish–Lithuanian_War – https://en.wikipedia.org/wiki/Polish–Czechoslovak_border_conflicts – They then, as they do today, dreamt of the Intermarium. https://en.wikipedia.org/wiki/Intermarium – And in 1938 following the Munich destruction of Czechoslovakia they ripped Teschen out of the dying corpse of Czechoslovakia. "At noon on 30 September, Poland gave an ultimatum to the Czechoslovak government that demanded the immediate akia evacuation of Czechoslovak troops and police and gave Prague time until noon the following day. At 11:45 a.m. on 1 October the Czechoslovak foreign ministry called the Polish ambassador in Prague and told him that Poland could have what it wanted. The Polish Army, commanded by General Władysław Bortnowski, annexed an area of 801.5 km2 with a population of 227,399 people. The Germans were delighted with the outcome.[citation needed] They were happy to give up a provincial rail centre to Poland. It was indeed a small sacrifice, spread the blame of the partition of Czechoslovakia, made Poland an accomplice in the process and confused the issue as well as political expectations. Poland was accused of being an accomplice of Nazi Germany." https://en.wikipedia.org/wiki/Polish–Czechoslovak_border_conflicts