1. Louisiana Purchase Treaty signed in 1803: On April 2, 1803, the Louisiana Purchase Treaty was signed by the United States and France, which marked the transfer of Louisiana Territory from France to the United States. This land acquisition doubled the size of the United States and opened up vast territories for exploration, settlement, and development.

2. Huey P. Long born in 1893: Huey P. Long, one of the most influential politicians in Louisiana history, was born on April 2, 1893, in Winnfield, Louisiana. He served as Governor of Louisiana and then as a United States Senator, promoting his "Share Our Wealth" program and advocating for the New Deal policies of President Franklin D. Roosevelt.

3. Statehood achieved in 1812: Louisiana achieved statehood on April 30, 1812, becoming the 18th state in the United States. This event marked the end of the Louisiana Territory's long journey from French colony to American state.

4. Battle of Shiloh in 1862: The Battle of Shiloh, one of the most significant battles of the Civil War, began on April 6, 1862, near Shiloh, Tennessee. Many soldiers from Louisiana fought in this battle, including the famed Louisiana Tigers, who suffered heavy casualties.

5. First Jazz Fest held in 1970: The first New Orleans Jazz & Heritage Festival, also known as Jazz Fest, was held on April 22, 1970, in Congo Square. This festival has become a beloved annual event that celebrates the music, food, and culture of New Orleans and Louisiana.