Porfirio Díaz was a Mexican president in the late 1800s and early 1900s. He was a successful soldier and very intelligent, but he was also very controlling. He wanted to make Mexico a powerful country and he tried to do this by making everyone follow his rules. He kept Mexico peaceful and wealthy, but it meant that he was very strict. He was also very corrupt and he got wealthy while many Mexicans stayed poor. After he had been president for a long time, many Mexicans wanted him to resign and they had a revolution. In the end, he had to leave Mexico, and a new president took his place.