Mexico has dealt a couple of blows to the Chinese in the past few months, but it wasn’t the first time.

It was in May 1911 that the army massacred at least 300 Chinese immigrants in Torreón — half the Chinese population, a slaughter that has since been blamed on racial intolerance and hatred.

Like some other Mexican massacres, it was also covered up.

But an uncovering is taking place this week in Mexico City in the form of an exhibition entitled “303: the Chinese massacre in Torreón,” a collection of photos, documents and video that focus on a historical event that doesn’t appear in any history texts.

It took place during the height of the revolution, when Francisco Madero’s army took control of the city. By three o’clock in the afternoon of May 15 the streets were covered in bodies.

The exhibition is being presented by the Museum of Memory and Tolerance, whose director of expositions, Linda Atach, described the massacre as “a stain on the nation’s history.” She says it is a moment in history that is not mentioned in school textbooks, and highlighting it now is timely considering the issues surrounding the migration of Central Americans.

The Chinese had come to Mexico to work, and were building railways across the country. But anti-Chinese laws followed and many were persecuted, particularly in the north, said Atach.

The Chinese community in Torreón had been regarded with mistrust and xenophobia due to the prosperity of its businesses, according to the show’s curators, Adriana Gallegos and Carlos Castañón.

What happened in Torreón should sound an alert and focus attention on the current situation, Atach said, referring to the plight of migrants.

Chinese interests in Mexico have been given a hard ride since President Peña Nieto revoked plans to award a high-speed train contract to a Chinese firm in November, a project that was shelved last week. Also last week, a huge Chinese trade center, Dragon Mart Cancún, was also shuttered.

But it’s unlikely that xenophobia had anything to do with either decision.

Sources: El Siglo de Torreón (sp), EFE (en)