1. Billy the Kid was tried and convicted on March 18, 1881, in Mesilla, New Mexico for the murder of Sheriff William Brady. This was one of the most famous trials in New Mexico history, and Billy the Kid was sentenced to hang. However, he escaped from jail in April and was killed later that year.

2. New Mexico became the 47th state of the United States on March 18, 1912. This was a significant moment in the state's history, as it had previously been a territory for over 60 years.

3. On March 18, 1942, the United States government established the Kirtland Air Force Base in Albuquerque, New Mexico. The base is still active today and is an important part of the state's economy.

4. The Navajo Code Talkers, a group of Native American soldiers who used their language as a code during World War II, were honored by the state of New Mexico on March 18, 2002. The state declared that day "Navajo Code Talkers Day" in recognition of their service.

5. The first female mayor in New Mexico history, Soledad C. Chacon, was elected on March 18, 1922, in Santa Fe. Chacon served two terms as mayor and was an advocate for women's rights and social justice. Her election was a significant milestone for both the state and the country.