Todayâs Highlight in History: On April 12, 1945, President Franklin D. Roosevelt died of a cerebral hemorrhage in Warm Springs, Georgia, at age 63; he was succeeded by Vice President Harry S. Truman. On this date: In 1861, the Civil War began as Confederate forces opened fire on Fort Sumter in South Carolina. In 1877, the catcherâs mask was first used in a baseball game by James Tyng of Harvard in a game against the Lynn Live Oaks. In 1955, the Salk vaccine against polio was declared safe and effective. In 1961, Soviet cosmonaut Yuri Gagarin became the first man to fly in space, orbiting the earth once before making a safe landing.