Following the events of the Second World War, Germany was split in half—a Western and an Eastern Part—for almost 40 years. But in May of 1989, Hungary removed its border fence with Austria, cutting a hole into the Iron Curtain, the (not so) imaginary boundary that divided Europe from the USSR. Thousands of East Germans took this opportunity to leave their homes behind and flee to the West. Following this massive exodus and inspired by revolutions in nearby countries, such as Poland, protests in East Germany started to arise, calling for change. By November of the same year, even the Berlin Wall, perhaps the ultimate symbol of a divided Germany, began to crumble and fall.
Image Source: Bundesarchiv, Bild 183-1990-1003-400 / Grimm, Peer / CC-BY-SA 3.0
These events and the unwavering call for freedom led to the first free elections of the German Democratic Republic in March 1990. The future was now in motion, and the negotiations between West and East Germany cumulated in a promise of unification. A complex matter, but eventually, Germany was officially unified on October 3, 1990, which has been the German national holiday ever since.