1918 – 1920 · Camp Funston, Kansas, an early documented outbreak
Background
An influenza A pandemic spreads worldwide and causes tens of millions of deaths. The name Spanish flu reflects the visibility of Spanish reporting, not a proven origin in Spain; its precise origin remains uncertain.
Estimates & margins
Deaths17m – 50m
Global mortality is uncertain because records are incomplete; much literature cites about 50 million, though lower estimates have been published.