The team was founded on November 4, 2015, one of the four original franchises of the LFA. The team hoped to draw fans from the local university, Instituto Politécnico Nacional. The IPN football team, the Águilas Blancas, were one of the most popular teams in ONEFA and their team colors are cherry and white. For these reasons, the LFA franchise chose Eagles as their nickname and adopted similar colors of red and white. Antonio Sandoval was hired as the Eagles first head coach. The Eagles played their first game of the inaugural LFA season on February 21, 2016, falling 30-28 against the Condors. The Eagles would get their first victory seven days later, defeating the Raptors 29-27. Finishing with a record of 3-3 in their first season, the Eagles fell short of qualifying for the playoffs. José Campuzano replaced Sandoval as head coach for 2017. In his first year, he led the Eagles to a 4-3 record, and an appearance in the playoffs. But in the Central Division Championship Game, the Eagles were crushed by the Mayas, 40-18. In its first two seasons, all LFA teams were directly administered by the league. Prior to the 2018 season, the LFA decided to allow the franchising of its teams. On October 5, 2017, the Eagles were acquired by Marco Antonio Conde, director of the Universidad del Conde de Coatepec, Veracruz. With the arrival of Conde, the Eagles were renamed as Mexicas, a nickname used by the sports teams of the aforementioned university. The team colors of red and white were changed to red and black. With a new nickname and new team colors, the team also had yet another new head coach to open a season. Rafael Duk equaled the previous season results, taking the Mexicas to a 4-3 record. The team generated controversy by refusing to play in Week 3 against the Dinos Saltillo, after a serious knee injury to wide receiver Mubalama Massimango that occurred in Week 1, and was not properly attended to by the LFA. Although the league recognized that there was an administrative problem with the medical expenses insurance policy, the team was punished for its forfeit, and had to pay a fine of $657,820.00 MXN, and would have to change their franchisee for the 2019 season. Despite the controversy, the team on the field excelled. Unlike the 2017 team that stumbled in the playoffs, the Mexicas were able to win the Central Division Championship Game by defeating the Mayas 27-17. On April 22, 2018 at Estadio Azul, the Mexicas made the most of their first appearance in the Tazón México, shutting out the Raptors 17-0 for their first LFA title. In September 2018, the new team franchisees announced they would to move the site of their home stadium to Campo del Casco de Santo Tomás starting with the 2019 season. In 2019, the team had its worst season since its inception, finishing with a 2–6 record and becoming the first defending champion to fail to qualify for the playoffs.
