1. The Battle of Monterrey began on August 21, 1846 during the Mexican-American War. The battle was fought between American forces led by General Zachary Taylor and Mexican forces under General Pedro de Ampudia. The battle was a decisive victory for the Americans and helped cement Taylor's reputation as a successful military commander.

2. On August 21, 1862, the Confederate General John C. Breckinridge marched his troops into Kentucky in an attempt to retake the state for the Confederacy. The move was unsuccessful and Kentucky remained loyal to the Union for the remainder of the war.

3. The first commercial oil well in Texas was drilled on August 21, 1866 in the town of Nacogdoches. The well produced about 10 barrels of oil per day and helped kickstart the Texas oil industry.

4. On August 21, 1914, the first passenger train arrived at the newly built Houston Union Station. The station was designed to be a hub for railroad traffic in Houston and was a symbol of the city's growing importance as a transportation center.

5. August 21, 1968 was the day that Hurricane Beulah made landfall on the Texas coast. The storm was one of the most destructive hurricanes in Texas history, causing widespread flooding and damage across the Rio Grande Valley. Despite the destruction, the storm also brought much-needed rain to the drought-stricken region.