The major Empires of the Western civilization are: Ancient Athens, Sparta, the Roman Republic, the Roman Empire, the Spanish Empire, the Portuguese Empire, the British Empire, the Dutch Empire, the French Empire, and the American Empire. The common feature of these empires is that they were founded on slave labor.
The number of slaves in Ancient Athens, the so-called bastion of philosophy and democracy, was ten times more than the citizens. Aristotle has posited that without slave labor an intellectual life is not possible. In the Roman Republic and the Roman Empire the slaves were ten to fifteen times more than the citizens. Wherever the Roman military went, the Roman slave traders followed. Whenever the Romans won a battle, the defeated side was sold to the slave traders. For 600 years, the Romans held their gladiator spectacles in which thousands of slaves were butchered—no other civilization has forced its slaves to fight to the death for the entertainment of the masses.
From the 1440s to the 1860s some 12–15 million Africans were brought to North and South America in chains and made to labor in the mines and plantations. This was the largest forced migration in history. All the European imperialist powers—Spain, Portugal, England, France, and Holland—profited from the slave trade. It is estimated that more than 750,000 slaves from Africa were brought to the thirteen colonies of the United States. In 1660, the British Monarch Charles II granted the monopoly on Atlantic slave trade to the Royal African Company. His brother James II was the commander of the company before he ascended to the throne of Britain in 1685—the irony, a slaver became the King of England.
The Western empires tend to fall when they lose control of their slaves. The Athenians and the Spartans were weakened by their slave rebellions The Roman Republic fell within 50 years of the great slave revolt led by Spartacus. The Roman Empire fell after the Goths, Gauls, Vandals, Alans, and other tribes of Europe united into a militaristic group which went to war against Rome. The empires of Spain, Portugal, England, France, and Holland fell when their colonies started fighting for independence. The American empire has started declining after the Civil Rights movement of the 1950s and 60s.