1. On March 31, 1836, the Convention of 1836 formally adopted the Texas Declaration of Independence, declaring Texas as a free and independent republic from Mexico.

2. On March 31, 1842, the Battle of Mier, a brutal engagement between Texan forces and Mexican troops, ended in a decisive Mexican victory. The fighting involved hand-to-hand combat, bayonet charges and brutal street fighting.

3. On March 31, 1931, the first ever Texas State Optical Convention was held in Houston, Texas. This event marked the birth of the largest independent optometric association in America.

4. March 31, 1927 saw the passing of Johnny Horton. The Texan country singer and songwriter rose to fame in the 1950s and 60s for his hits including "The Battle of New Orleans" and "North to Alaska."

5. On March 31, 2006, the Texas Supreme Court unanimously struck down the state's ban on gay sexual relations, ruling that the law violated the Fourteenth Amendment's guarantee of equal protection under the law. This marked a landmark victory in the struggle for LGBTQ rights in Texas.