The bowler hat is a hard felt hat with a rounded crown.
It was originally designed to protect the head from blows. One story is that the British soldier and politician Edward Coke, the younger brother of the 2nd Earl of Leicester had it made in 1849. Its purpose was to protect his gamekeepers' heads from low-hanging branches while on horseback. The keepers had previously worn top hats, which were easily knocked off and damaged.