The Empire was created because Darth Sidious overthrew the Galactic Republic by starting the Clone Wars. Before the war started, many planets and star systems left the Republic to create their own government and army, the Separatists. Many people in the Republic were scared of the Separatists, so they voted to give emergency powers to Supreme Chancellor Palpatine, the public identity of Darth Sidious. This was because he was well-liked and they believed he was a strong leader. By the end of he war, Sidious could create any law he wanted. The only ones who could stop him were the Jedi, a very old group of knights who swore to protect the Republic. They tried to arrest him, but they failed. Sidious used this as an excuse to create a government with much more security. He made the Republic into the Empire, and made himself Emperor.