Two revolutions ran through this century and a half, braided together, and the world you live in is their child. The first was political. The idea you met at the start of the civics flyover — that governments get their power from the consent of the governed — stopped being a philosopher’s claim and started toppling thrones. British colonists went first, in 1776. France followed in 1789, and a kingdom a thousand years old took apart its own monarchy in the name of liberty and equality.
And then came the revolution that took the era’s words most seriously of all. In 1791, in the French sugar colony of Saint-Domingue — the richest colony on earth, worked by half a million enslaved Africans — the enslaved rose. Through thirteen years of war they defeated the local slaveholders, then British and Spanish invasions, then the army of Napoleon himself, and in 1804 declared the independent republic of Haiti: the hemisphere’s second independent nation, and the first anywhere to be born of a successful revolution of enslaved people. Every power holding slaves worked to isolate and punish the young country — which tells you exactly how loudly its example spoke. If your roots run to Haiti, this is your ancestors’ page, and the age’s largest promise was cashed first by them. In the decades after, led by Bolívar and others, most of Spanish America broke free as well; by the 1820s the Atlantic’s map of empires had cracked from Boston to Buenos Aires.
The second revolution had no declaration and no flag. In Britain, in the late 1700s, coal, steam engines, and machines began doing what muscles — human and animal — had always done, and doing it tirelessly. This was the Industrial Revolution: energy from fossil fuels unlocked at scale for the first time, an event as large, in this course’s long view, as farming itself. Factories rose, railroads and telegraphs annihilated distance, world population passed its first billion around 1800 and began to climb, and two new classes faced each other across the factory floor — owners of the machines, and the men, women, and children who tended them for wages. Out of their collision came the century’s new struggles: unions, strikes, socialist movements, and the fights over hours, safety, and pay whose American chapters you read in Movements Three and Six.
Then the two revolutions combined into something darker. Nations armed with industry — Western Europe, later the United States and Japan — turned machine power into empire on a scale never seen: by 1900 they had seized nearly all of Africa (carved up at a Berlin table you visited on the borders page) and much of Asia. Colonies were worked as suppliers of raw materials and captive markets for machine-made goods — a world economy rigged toward its center. And everywhere, from the first day, it was resisted — a resistance that becomes the main story of the final page.
Hold the century’s contradiction in one hand: it declared all men created equal, and it industrialized domination. Both are true, both are inherited, and the next page is the world sorting out which one wins.