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Here are five interesting facts about March 18 in Louisiana history:

1. In 1803, the Louisiana Purchase Treaty was ratified by the US Senate, which provided for the acquisition of Louisiana by the United States from France for $15 million. This acquisition greatly expanded the territory of the young nation and shaped the future of Louisiana.

2. In 1837, New Orleans was struck by a devastating fire that destroyed nearly all of the city's business district. The fire, which began at a cotton warehouse on the corner of St. Louis and Chartres streets, quickly spread thanks to strong winds and a lack of fire hydrants.

3. In 1851, the Louisiana State Seminary of Learning and Military Academy, now known as Louisiana State University, was founded in Pineville, Louisiana. The school was established to provide education and military training to the state's youth.

4. In 1927, the Mississippi River flooded in what was one of the worst natural disasters in American history. The flood covered over 16 million acres of land, caused billions of dollars in damage, and displaced hundreds of thousands of people.

5. In 1974, a major refinery explosion occurred in Baton Rouge, killing 17 people and injuring more than 100. The explosion led to a massive fire that burned for hours and caused significant damage to the surrounding area. The cause of the explosion was determined to be a failure in the refinery's cooling system.