1. Civil War: The Battle of Irish Bend occurred on April 20, 1863. Confederate forces, led by General Richard Taylor, won a strategic victory against Union forces attempting to capture the key port city of New Iberia. The battle resulted in approximately 400 casualties and is regarded as one of the most significant battles fought in Louisiana during the Civil War.

2. Jazz Fest: The New Orleans Jazz & Heritage Festival, also known as Jazz Fest, is a ten-day music festival held annually in New Orleans. The festival was first held on April 20, 1970, and has since become a staple event in Louisiana's cultural calendar. Jazz Fest showcases a variety of music genres, including jazz, blues, gospel, Cajun, and zydeco, and attracts over 400,000 attendees each year.

3. Natural Disaster: On April 20, 2010, the Deepwater Horizon oil rig in the Gulf of Mexico suffered an explosion and subsequent oil spill that would become one of the worst environmental disasters in history. The spill initially released an estimated 210 million gallons of oil into the Gulf, causing widespread damage to marine life and coastal ecosystems. The disaster continues to impact the region today.

4. Political Corruption: On April 20, 1972, Louisiana Congressman F. Edward Hebert was indicted on charges of bribery, kickbacks, and conflict of interest. Hebert, who had served in the U.S. House of Representatives since 1941, was accused of accepting illegal payments from defense contractors in exchange for government contracts. Hebert eventually pleaded guilty and was sentenced to three years probation, making him one of the highest-ranking officials ever convicted of political corruption.

5. Sports: On April 20, 2002, the New Orleans Hornets played their first playoff game in franchise history. The Hornets, who had relocated from Charlotte, North Carolina, two years earlier, faced off against the Charlotte Hornets in the first round of the NBA playoffs. Despite losing the series 3-1, the playoff appearance was a significant moment for the young franchise and helped solidify the team's place in the New Orleans sports landscape.