May 5, 1862: The French were heavy favorites that day, as it was long before they went on their losing streak in international competition.
Sportsbooks don't keep odds that far back, but the troop ratio was probably about 2-to-1. Still, Mexico won the Battle of Puebla in just a matter of hours.
Entirely neglected is the fact that the French, who returned a year later with 30,000 troops, won the rematch. But historical accuracy isn't the point here. Like many holidays, this, too, evolved as a marketing opportunity.
By the dawn of a new millennium, Cinco de Mayo was a mostly American phenomenon: a show of ethnic pride, a chance for families to get together and a moment for corporations to sell stuff on a party weekend. There were also, on occasion, some boxing matches. Julio Cesar Chavez's 1994 rematch with Frankie Randall comes to mind.
But it wasn't until 2003 that anyone in the sport really saw the potential for Cinco de Mayo. That's when Oscar De La Hoya, wearing his newfound promoter's hat, sought to turn his otherwise ho-hum fight with Yory Boy Campas into a kind of boxing holiday.
"To be honest," De La Hoya told Arash Markazi years later, "my hope was for it to become what it has become." The erstwhile Golden Boy -- who, like the holiday itself, was more popular in the States than in Mexico -- was referring to Cinco de Mayo's now-accepted standing as boxing's Super Bowl weekend.
To be sure, the date has seen some great fights. The following year marked the first installment of the Manny Pacquiao-Juan Manuel Marquez tetralogy. In '05, it was Diego Corrales knocking out Jose Luis Castillo -- not merely the greatest of all Cinco de Mayo fights, but arguably as compelling a 10 rounds as the sport has ever seen.
But De La Hoya's vision would come to pass only at De La Hoya's expense, with boxing's first Mexican-American superstar in the unlikely role of foil. Put another way: What Oscar could do, Floyd could do better.
In his maiden voyage at junior middleweight -- May 5, 2007 -- Floyd Mayweather won more than the WBC title. He transformed not merely his image (from "Pretty Boy Floyd" to his "Money Mayweather" persona) but the game itself. By the time he appeared for his marvelously provocative ring walk -- in an enormous white sombrero and wearing the colors of the Mexican flag -- Mayweather was more hated than the French in 1862.
"I knew I was going to beat Oscar and make all the Mexican fans my fans, too," Mayweather recently told ESPN. "I always had a way of getting noticed."
But there was another motive, too.
"It was to honor my Uncle Roger," he said via email.
In the great Southern California boxing venues -- the Grand Olympic Auditorium, the Los Angeles Memorial Sports Arena and The Forum -- Roger Mayweather was known as "The Mexican Assassin." He was partial to a black sombrero, worn most famously for a 1989 loss to Chavez. A decade later, he retired with a record of 59-13 before embarking on his best-known role: his nephew's trainer.
If De La Hoya fancied himself Chavez's successor, then Floyd Mayweather would play his uncle's avenger. Roger Mayweather died in March after a long illness. But judging from his nephew's recent social media posts and the way Floyd has acknowledged the deep connection that bound them, you can't help but wonder if the sombrero homage was more personal than Floyd ever let on.
No, he insisted: "To be a great, successful fighter you can't go into the ring with personal feelings. It doesn't work. Everything I did throughout my career was to become the best ever, and all the business moves I made helped me get there. It was always about business."
As it happened, whether you loved him or loathed him, "Money Mayweather" would prove the most lucrative role in the history of sports. Not only did De La Hoya-Mayweather do a then-record 2.4 million pay-per-view buys, it established Cinco de Mayo as the near-perfect boxing date.
It was that rare weekend that offered no competition: no football, no college ball, nothing save for a possible second-round NBA or NHL playoff game. "It's become so much more than a boxing match," said Chris Baldizan, senior vice president of entertainment and marketing for MGM Resorts International. "It takes over our properties and our city. It's become a signature weekend for Las Vegas."
Unlike the Super Bowl or the Final Four, he said, "For boxing you have to be here. Cinco de Mayo and boxing have become synonymous."
It has become an annual showcase for boxing's biggest reigning attraction, pounds for dollars the best fighter in the world. And while boxing is rooted in ethnic rivalry, seven of the past 11 Cinco de Mayo fights featured no Mexican fighter at all. Manny Pacquiao fought in four of them, including the date's most devastating knockout, that of Ricky Hatton in 2009, a single sledgehammer left that was the beginning of the end of Hatton's career.
Still, the records belong to the undefeated Mayweather:
Six fights, most of them against Hall of Fame-caliber opponents
11.8 million PPV buys
$138.5 million in live gates
$289 million in personal payouts
"I turned Cinco de Mayo into Cinco de Mayweather," he said.
If the emphasis on money feels unseemly to fans of regular sports, remember that Mayweather comes from a family of fighters. He knew what typically happened to fighters, and he made it his business to succeed in exploiting the game better than it could ever exploit him.
So toward that end, Mayweather-Pacquiao in 2015 became the richest fight ever. With 4.6 million PPV buys, it was a historic bore. What's more, it obscures better and more entertaining tests on Cinco de Mayo weekends. In 2010, Mayweather took a right hand from Shane Mosley that another fighter wouldn't have survived. In 2014, there was a close, rugged decision over Marcos Maidana.
Five years after Mayweather's last Cinco de Mayo fight, you wonder if those who once jeered him in his sombrero have come to miss him.
"All the fans miss me," he said. "... But I miss my fans, too."
Even -- or perhaps, especially -- those who rooted against him.
That brings us to what might have been this year: Canelo Alvarez (yet another Mayweather victim) likely to fight Billy Joe Saunders. It could have been a pretty good fight, actually, as Saunders, with some skills and a 168-pound belt, had a lot better chance than the French.
"I'm proud to represent my country on important dates such as this one," Alvarez said during the lead-up to his first Cinco de Mayo fight in 2016. "We'll be chanting 'Viva Mexico' together."
Perhaps this was as intended, a holiday headlined by a Mexican champion. Just remember: If Cinco de Mayo now belongs to Canelo, it was gifted by the only man to defeat him.