Normally, the Classic period in Mesoamerica is characterized as the stage in which the arts, science, urbanism, architecture, and social organization reached their peak. This period was also dominated by the influence of Teotihuacan throughout the region, and the competition between the different Mesoamerican states led to continuous warfare.
The most common name for the killer virus, the Spanish flu, implied, of course, that it originated in Spain. Perhaps this was because there were serious outbreaks in both Madrid and Seville that infected eight million people in May of 1918 alone, even almost taking out the king himself, Alfonso XIII.
The deadly Spanish flu claimed more lives than World War I, which ended the same year the pandemic struck. Now, new research is placing the flu's emergence in a forgotten episode of World War I: the shipment of Chinese laborers across Canada in sealed train cars.