The significance of the defeat at Waterloo in 1815 for Napoleon Bonaparte was monumental, as it marked the end of his rule and the final collapse of his empire. Following his return from exile, Napoleon’s failure at Waterloo led to his second abdication and banishment to Saint Helena, where he spent the remainder of his life. The battle redefined the power dynamics in Europe, leading to the establishment of the Congress of Vienna and a new balance of power that aimed to prevent future conflicts.