According to legend, the town and the Purgatoire River were named after a group of conquistadors, probably part of Coronado's expedition, who died without the last rites sacrament of a priest.

The original Spanish name for Las Ánimas ("The Souls," in Spanish) was purported to be[citation needed] La Ciudad de Las Ánimas Perdidas en Purgatorio, "The city of lost souls in Purgatory."

Developers and municipalities have capitalized upon drought and low crop prices by buying water from desperate farmers.

As this water is diverted upstream to serve the larger cities, Las Animas loses access to this important resource.

[citation needed] Las Animas is located in northwest Bent County at 38°4′1″N 103°13′33″W / 38.06694°N 103.22583°W / 38.06694; -103.22583 (38.066980, -103.225937),[12] along the Arkansas River.

On the other end of the spectrum, Las Animas’ hottest minimum temperature occurred August 2, 1935, with a low of 89 °F (31.7 °C).

Las Animas sits along the Mountain Branch of the Santa Fe Trail and served as the major city in southeast Colorado until the Atchison, Topeka and Santa Fe Railroad established operations in La Junta, 20 miles (32 km) to the west of Las Animas.

The Las Animas High School Student Council organizes the day, with assistance from the Bent County Chamber of Commerce.

Festivities have included a parade, a costume contest, square dancing, a demolition derby, and a traditional "Ranchburger" lunch, as well as many other activities.

•April 24, 2009, Las Animas celebrated its 75th Annual Santa Fe Trail Day with special guests, those who previously were the Santa Fe Trail Day Crowned Queen and those who had been previously elected Student Council President, as far back as 1944 attended.

In 2004, it was added to the National Register of Historic Places because of its significance, and, needing renovation for continued use, it was on the 2004 Colorado Preservation, Inc.

[18][19][20][21] As attempts were made to preserve the building, a modern facility was built to the west, inhabiting what was the playground and open area for the now demolished original structure.

Considered by the School Board and all but a handful of citizens to be too costly to renovate, this 90-year-old building was demolished on February 21, 2006.

[23] Notable individuals who were born in or have lived in Las Animas include fur trader and rancher William Bent,[24] actor and singer Ken Curtis,[25] and editor and arts patron Mari Yoriko Sabusawa.