The British pet massacre was an event in 1939 in which an estimated 400,000 cats and dogs, a quarter of England's pet population, were euthanized due to an aside in a pamphlet noting it as an option for people unable to take their pets with them when evacuating. The incident was recognized as unnecessary almost immediately after it occurred, stemming from social panic over the impending war, social conflicts on the role of pets, and the "black boredom" of people seeking a way to feel like they were contributing to the war effort, rather than any sort of actual necessity.
Background
During World War I, abandoned feral pets in London had become a major issue. In 1939, the British government, seeking to avoid a repeat of this, formed the National Air Raid Precautions Animals Committee (NARPAC) to decide what to do with pets before the war broke out. The committee was worried that when people evacuated, they might leave their pets behind. In response to that fear, NARPAC published a pamphlet titled "Advice to Animal Owners." NARPAC's messaging was primarily focused on evacuation, suggesting moving pets from the big cities and into...