Early humans may have held psychedelic cave raves, according to new research. The study suggests that ancient people used mind-altering substances and created art in caves to enhance their spiritual experiences.

A brief overview of the history of toilets, from ancient civilizations to modern times.

Gandhi’s Salt March was a nonviolent protest against British salt taxes in India. It involved a 240-mile march to the Arabian Sea where Gandhi and his followers made their own salt. The march sparked a wave of civil disobedience and helped India gain independence.

The Nazis planned to assassinate the leaders of the Allied powers during World War II, known as the Big Three.

Bartolomeu Dias was a Portuguese explorer who was the first European to sail around the southern tip of Africa, now known as the Cape of Good Hope, in 1488.

The Immigration Act of 1965 was a law that abolished the national origins quota system and allowed for more immigrants from non-European countries to enter the United States.

Kaiser Wilhelm II was the last German Emperor, who ruled from 1888-1918. He led Germany in World War I, until his abdication and exile abroad.