A new collection of recreated vintage Mexican baseball hats almost instantly sold out when it went on sale last week, illustrating the hunger fans have for uncovering the forgotten history of the ball game in Latin America.

The big picture: Historians, fans and activists in recent years have worked to uncover the history of the key roles Latinos in the U.S. played in the formation of the game.

Driving the news: Seattle-based Ebbets Field Flannels last week released a limited series of vintage baseball caps of teams from Mexico that played from 1915 to 1940.

• The hats are from forgotten teams like the Comintra Tigers of 1937 and the Heroico Colegio Militar of 1915, whose origins are now largely unknown.
• Ebbets Field Flannels founder Jerry Cohen told Axios the launch was "one of the most successful releases we've ever done."

Background: Baseball in Mexico grew out of teams formed by companies, political parties and military units before an official league was created.

• Teams were made up of players from Cuba, Mexican towns and the American Negro League. Mexican baseball did not have Jim Crow laws that banned Black players.
• Later, loosely affiliated Mexican American teams formed in the U.S. would play against Negro League teams and others made up of Asian American players.
• Cuba and Puerto Rico also had strong teams that developed players and generations of fans.

Cohen told Axios he got interested in Mexican baseball history after visiting his friend Tomas Morales, the late dean of Mexican baseball writers, in the early 1990s.

• He then stumbled upon an online archive of 4,000 photos of Mexican baseball teams with beautiful logos and uniforms, but many shots didn't have captions.
• Cohen shared photos online and cross-checked with the Mexican Baseball Hall of Fame. Still, the origins and history of some teams remain mysterious and took some research.
• For example, the Heroico Colegio Militar logo appears to be an Indigenous petroglyph, but belonged to one of the country's most prestigious military academies.
• Cohen recreated the caps using the archive photos and oral histories to resemble their origin conditions closely.

Between the lines: A bilingual baseball exhibit on Latinos' historical connections to the game opened at the Smithsonian National Museum of American History last year and is on tour now.

• Exhibit organizers began collecting objects and oral history across 14 states, Washington, D.C., and Puerto Rico five years ago.
• The exhibit contained uniforms of Mexican American players who worked on Colorado and Wyoming farms starting in the 1920s, and who would later play against Japanese American teams in World War II-era detention camps.

Of note: More than 30% of Major League players are Latino, and the league's fanbase is becoming more diverse.

• Minor League Baseball in 2017 launched Copa de la Diversión, an initiative that gives 76 teams Latino-themed logos and names on certain nights to generate Latino fan interest.
• Teams like Fresno Grizzlies in California transform into the Lowriders de Fresno and the San Antonio Missions change into the Flying Chanclas de San Antonio.
• Since its inception, the program has increased the fan-to-attendee ratio by nearly 2%, amounting to more than a million tickets sold to U.S. Latinos alone, the league said.

What's next: Cohen said Ebbets Field Flannels is designing 15 to 20 different vintage caps from unknown Mexican teams and is looking for help identifying their history.

• Cohen said he's considering a series on Mexican American teams and is looking into another on West Coast teams involving Asian American players before World War II.

Editor's note: This story has been corrected to show that the Heroico Colegio Militar hat appears to feature a petroglyph (not the Comintra Tigers hat)