An empire is a large territory that includes many different lands and peoples, all controlled by a single powerful government or ruler. When one nation conquers or dominates other regions, bringing them under its authority, it creates an empire. The Roman Empire stretched from Britain to Egypt, ruling millions of people who spoke different languages and followed different customs. The British Empire once controlled territories on every continent, which is why people said “the sun never sets on the British Empire.”

Empires throughout history have been built through military conquest, colonization, or political domination. An emperor or empress often rules an empire, though some empires have been governed in other ways. The Mongol Empire, led by Genghis Khan, became the largest contiguous land empire in history by conquering vast territories across Asia and Europe in the 1200s.

While ancient and historical empires shape much of what we study in history class, the word can also describe powerful modern organizations or businesses. Someone might call a successful company owner who controls many businesses a “media empire” or a “shipping empire,” meaning they have vast influence and control in their field.

Empires rise and fall: they grow powerful, then eventually decline as they become too large to manage, face rebellions, or meet stronger opponents. Understanding empires helps us make sense of how our modern world developed, since the empires of the past created many of today's national borders, languages, and cultural connections.