Rats and mice were a major problem on ships because they ruined the crew’s food, chewed through equipment, and spread disease. Cats, with their predatory prowess, were a cheap and effective solution to any vermin infestation. The U.S. government, in an effort to protect documents from nesting rats, began to purchase clowders of cats in the 19th century, eventually supplying them to the U.S. Navy. In the United Kingdom, one of the earliest and largest cat rescue programs occurred during the First World War, when thousands of strays were rounded up in cities and given to the military. The cats supplied to the Royal Navy even received a weekly “victualing allowance” of 1 shilling and 6 pence to pay for treats from the ship’s canteen.