1. The Louisiana Purchase Treaty, which transferred ownership of the Louisiana territory from France to the United States, was signed on February 20, 1803. The Louisiana Purchase dramatically expanded the size of the United States and set the stage for westward expansion.

2. On February 20, 1864, the Confederacy commissioned the C.S.S. Louisiana, a massive armored ram designed for river warfare. Although the ship was never completed, it represented the Confederacy's innovative approach to naval warfare during the Civil War.

3. The first parade of the Mardi Gras season, the Krewe of Argus, takes place in New Orleans on February 20 each year. The parade typically features elaborate floats, marching bands, and colorful costumes.

4. In 1917, the United States Army opened Camp Beauregard near Alexandria, Louisiana. The camp served as a training ground for soldiers during World War I and has since been used for military training and disaster response operations.

5. On February 20, 1974, Patricia Highsmith, a prolific author best known for her psychological thrillers, died in Switzerland. Highsmith was born in Fort Worth, Texas, but spent much of her life living and working in Europe. Her most famous work, "The Talented Mr. Ripley," has been adapted into several successful films.