1. Louisiana Purchase: On July 30, 1803, the Louisiana Purchase Treaty was signed in Paris, France, which gave the United States ownership of Louisiana Territory from France for $15 million. This acquisition doubled the size of the young nation and greatly expanded its influence in North America.

2. Hurricane Betsy: On July 30, 1965, Hurricane Betsy hit Louisiana, causing major damage to New Orleans and the surrounding area. The storm resulted in 76 deaths and over $1 billion in damages at the time, making it one of the costliest hurricanes to hit the United States.

3. Huey P. Long Assassination: On July 30, 1935, Louisiana Senator Huey P. Long was assassinated in Baton Rouge. Long, known for his populist policies and charismatic personality, had been a major political figure in Louisiana and was seen as a potential presidential candidate before his untimely death.

4. Louis Armstrong Birthday: Jazz legend Louis Armstrong was born on July 30, 1901, in New Orleans. Armstrong, nicknamed "Satchmo," is still widely regarded as one of the most influential musicians in history, and his unique style and skill on the trumpet helped to shape the sound of jazz for generations.

5. Sherman's March: On July 30, 1864, Union General William T. Sherman began his famous march through Louisiana during the Civil War. The march, which started in New Orleans and ended in Georgia, was a major part of the Union's strategy to cut off Confederate supply lines and weaken their army. The march resulted in major destruction and economic damage to the South, but also helped to bring an end to the war.