World War II: The Burning of the Riga synagogues: The Great Choral Synagogue in German-occupied Riga is burnt with 300 Jews locked in the basement.

World War II or the Second World War was a global conflict between two coalitions: the Allies and the Axis powers. Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks and aircraft played major roles, enabling the strategic bombing of cities and delivery of the first and only nuclear weapons ever used in war. World War II is the deadliest conflict in history, causing the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Germany, Austria, Japan, and Korea were occupied, and German and Japanese leaders were tried for war crimes.

The burning of the Riga synagogues occurred in 1941, during the first days of the Nazi German occupation of the city of Riga, the capital and largest city in the country of Latvia. Many Jews confined in the synagogues died in the fires. Many other anti-Semitic measures were launched at the same time, ultimately followed by the murder of the vast majority of the Jews of Latvia.

Riga is the capital, primate, and largest city of Latvia. Home to 591,882 inhabitants, the city accounts for a third of Latvia's total population. The population of Riga metropolitan area, which stretches beyond the city limits, is estimated at 847,162. The city lies on the Gulf of Riga at the mouth of the Daugava river where it meets the Baltic Sea. Riga's territory covers 307.17 km² (118.60 sq mi) and lies 1–10 m (3–33 ft) above sea level on a flat and sandy plain.