Ethnic Poles in Czechoslovakia demanded autonomy for Polish minority. Poles formed the largest ethnic group in Cieszyn Silesia in the 19th century, but at the beginning of the 20th century the Czech population increased rapidly thereby placing the Poles in the minority. Initially, the Czechs and Poles collaborated on resisting Germanization, but this collaboration ceased after World War I. After the Polish-Czechoslovak War in 1920 the region of Zaolzie was incorporated into Czechoslovakia. The period between 1918 and 1920 experienced a great deal of tension and hostility. The decision was made to hold a plebiscite to settle which country would gain Cieszyn Silesia. A state of emergency ensued in May 1920 and gave rise to mutual intimidation, acts of terror, beatings, and even killings. By July 1920 both sides renounced holding a plebiscite and entrusted the decision with the Conference of Ambassadors. The Spa Conference decided to grant 58.1% of the area of Cieszyn Silesia and 67.9% of the population to Czechoslovakia. It was this division that gave rise to the birth of the Zaolzie region. In 1938 it was annexed by Poland in the context of the Munich Agreement and in 1939 invaded by Nazi Germany.
Wincenty Witos served three times as Premier of Poland, in 1920-1921, 1923 (Chjeno-Piast), and 1926. He co-founded the People's Party, and was one of the leaders opposing the Sanacja (Sanation) government. In 1926 the Witos government was overthrown by the May coup d'état led by Józef Piłsudski. Following his imprisonment, Witos lived in exile in Czechoslovakia from 1933. He returned to Poland on March 30, 1939, only to be imprisoned again months later by the invading Nazi Germans.
First trainloads of Jews from Paris arrived at Auschwitz. According to Yad Vashem, about 76,000 Jews from France were deported by train to the East, most of them from Paris, among them 11,000 children, all murdered upon arrival in Auschwitz. Most of the deportations left France from the concentration camp of Drancy. Deportations continued up until August 1944, even though the Allies had already begun to liberate France. Of all the Jews deported from France to the extermination camps in the East, a total of about 2,500 survived.)
The 2nd Shock Army of the 2nd Belorussian Front captured Danzig: Soviet Commander Rokossovsky began his final offensive on March 15, 1945. The fighting was savage, but by March 19 the Soviet spearheads had reached the heights over Zoppot, while the 4th Panzer Division had been pushed back to the outskirts of Danzig itself. By March 22, 1945, the 70th Army reached the sea, splitting the German defence. Gdynia was taken on March 26, 1945, its defenders and many civilians retreating to the headland at Oksywie, from where they were evacuated to the Hel Peninsula. Note: After the invasion of Poland by Germany on September 1, 1939, the Germans incorporated the Free City of Danzig into the newly formed Reichsgau of Danzig-West Prussia. Local SS and the police cooperated with the Germans with expelling Polish authorities from in and around the city. The Polish civilian Post Office employees, who had received military training and were armed, managed to defend the Polish Post Office for fifteen hours. Upon their surrender, they were tried and executed. ( In 1998, the sentence was officially revoked by a German court as illegal.) Polish military forces continued to fight in the city until September 7 and finally capitulated. The Allies at the Yalta Conference, of February 1945, agreed that the city would become part of Poland again.