The mandates were largely effective, although city officials, believing the worst was behind them, lifted restrictions. But a spike in cases after the New Year in 1919 prompted the Board of Supervisors to re-enact the mandatory mask ordinance. By that time, the patriotic fervor that influenced compliance had waned.

That’s when the Anti-Mask League was formed.

“People are tired of living under these restrictions, both the wartime restrictions as well as the epidemic control measures,” Navarro said. “That’s why that general grumbling about wearing masks spilled over into an actual organized protest movement in San Francisco.”

Navarro believes the group had only one meeting in late January, which was attended by about 2,000 people who did not wear masks (although organizers at the time claimed that the number was more than twice that). Mrs. EC Harrington, who was identified as the group’s chairman, urged the city Board of Supervisors to give residents “speedy relief” from the “burdensome” requirement, according to board’s meeting minutes.