William McKinley was the 25th President of the United States, born on January 29, 1843, and died on September 14, 1901. During his presidency, the United States experienced a period of industrialization and expansion, and he successfully led the Spanish-American War. McKinley pursued protectionist policies during his tenure, aiming to protect domestic industries through higher tariffs. Unfortunately, he was assassinated while in office, becoming the first U.S. president to be assassinated.