When was Napoleon defeated?

Napoleon was defeated at the battle of Waterloo on June 18, 1815. He was defeated by a coalition of nations consisting of Prussia, Britain and the Netherlands.Such was the magnitude of her defeat that the idiom ‘he/she has met their Waterloo’ signifies a personal disaster of great magnitude. 

Napoleon abdicated after his defeat, and coalition forces entered Paris on 7 July. The defeat at Waterloo ended Napoleon’s rule as Emperor of the French and marked the end of his Hundred Days return from exile. The abdication of Napoleon ended the  First French Empire and led to a relative period of peace and stability often referred to as the Pax Britannica.

For further reading check the following articles:

• The Renaissance
• Age of Enlightenment.
• French Revolution