Here’s a look at some interesting events that took place on this day in history:

1861 – The Civil War begins with Confederate forces firing on Fort Sumter, in the harbor of Charleston, SC (More info)

1945 – President Franklin D. Roosevelt dies while in office (More info)

1955 – The polio vaccine, developed by Dr. Jonas Salk, is declared safe and effective (More info)

1961 – Soviet cosmonaut Yuri Gagarin becomes the first human to travel into outer space (More info)

1992 – Euro Disneyland, later Disneyland Paris, opens (More info)