The Second World War began with the invasion of Poland. On the 1st of September 1939, Nazi Germany invaded Poland. As per the secret Molotov-Ribbentrop Pact, Soviet forces invaded and occupied East-Poland two weeks later. Read about Jewish refugees in Soviet-occupied Poland here.
Following the invasion and partition, the Polish government went into exile in London, where they were central in exposing the atrocities at Auschwitz to the rest of the world. More information on the Polish government-in-exile can be found here.
In June 1941, Nazi Germany violated the Molotov-Ribbentrop pact and attacked the Soviet Union. The Axis invasion of the Soviet Union was destructive and brutal: millions of soldiers and civillians died, food stores were burned, and infrastructure destroyed. Read an article on the Soviet-German War (1941-1945) or take a look at pictures of what Russians refer to as the Great Patriotic War. It was during this time that Germans occupied Rivne and made it the capital of the Ukrainian region.
Not long after Haya-Lea was deported to the Gulag, her remaining family in Rovno were killed. The Rovno Massacre, taking place throughout November 1941, claimed over 25,000 lives. This was carried out by the occupying German forces, with assistance from some of Rovno's Ukrainian population who collaborated with the area's Nazi authorities. Flip through this ebook for more information on wartime Rovno (focus on the second chapter, "Aktion: The Holocaust in Rovno", to learn about the Rovno Massacre).
Soviet forces beseiged and captured Berlin in April 1945, effectively ending the Second World War. In narratives of this event, the experiences of soldiers, civilians, and the military high commands differ significantly between Western and Soviet perspectives. Read a Soviet and an Allied account of the Seige of Berlin, and consider their similarities and differences.
Read here about Poland at the end of the war, and the political situation in Europe.