Here are 5 interesting facts about December 15 in Louisiana history:

1. The Louisiana Purchase was finalized on December 15, 1803, when France officially transferred its claim to Louisiana to the United States. This acquisition of over 800,000 square miles of territory doubled the size of the United States and greatly expanded its western frontier.

2. On December 15, 1920, the first commercial radio broadcast in the United States took place in New Orleans. The radio station, WWL, was operated by the New Orleans Times-Picayune newspaper and broadcasted from the top of the Maison Blanche building in downtown New Orleans.

3. Louisiana's salt dome oil industry began on December 15, 1901, when the first commercial oil well in Louisiana was drilled in the town of Jennings. This discovery led to the development of the state's petroleum industry, which today is the fourth-largest in the United States.

4. Louisiana's Pelican State redbud tree was designated the state tree on December 15, 1990. The Pelican State redbud is a small deciduous tree that is native to Louisiana and is known for its stunning pink and lavender flowers.

5. The USS Louisiana, a United States Navy submarine, was commissioned on December 15, 1990. The submarine is the fourth United States Navy vessel to be named after the state and is known for its distinctive "Lone Star" logo, which represents Louisiana's nickname as the "Pelican State."