Trotsky was Lenin’s second-in-command during the Russian Revolution, and later the first leader of the Red Army and a high-ranking Politburo member. But after the death of Lenin in 1924, he lost power and position to Stalin. In 1928, Trotsky was exiled to Alma Ata in Kazakhstan. A year later, he was expelled from the Soviet Union, and sent to Turkey, accompanied by his wife Natalia Sedova and his son Lev Sedov.
His exile marked the end of any serious internal opposition to Stalin in the Soviet Union, with most of his followers either fleeing the country or surrendering. Trotsky continued to advocate his opposition to Stalin from outside the country. A constant thorn in Stalin’s side, he was assassinated in Mexico by a Soviet agent in 1940.
The combined German and Russian invasions of Poland in September 1939 were disastrous for the Polish people. The Germans invaded on September 2, and the Poles fell back before the onslaught at first. (The Germans did not actually practice blitzkrieg in Poland, but the invasion was still a swift one.) The Poles ceded some territory, and fell back to defensive positions further east…
…and then, on the 17th of September, and without any formal declaration of war, the Soviets invaded from the east. Caught between two armies, either of which by itself was numerically superior to the Polish army, there was little chance of victory. Although Britain, France and their respective allies had entered the war on the Polish side, they could not deploy in time to give any assistance to their beleagured ally. The Poles fought hard, and inflicted great casualties on the Germans and Russians, but the result was never truly in doubt.
Although some units fought on, the war in Poland largely came to an end with the fall of Warsaw on September 27, 1939, and the Polish government in exile was officially formed on the following day.
It was the opening gambit of World War Two in Europe. After trying to press its geographical claims (especially to the Danzing corridor) through political means, Hitler decided to go ahead with an invasion of Poland.
Two weeks later, in accordance with the provision of a secret agreement between Nazi Germany and Soviet Russia, Stalin’s forces invaded Poland from the east, and within a month, the nation was conquered entirely, and partitioned between the two invaders.
But the war wasn’t over. Poland had allies – France, Britain and Britain’s Empire all declared war on Germany on September 3. World War Two had begun in Europe.