If by flush toilet we mean any toilet hi which water is used to clean the bowl after its use, then the flush toilet is close to 4,000 years old! The palace at Knossos, Crete, which was built around 2000 B.C., contained latrines that were cleaned by water stored in a reservoir and delivered to the bowl through pipes.
Houses built around the same time in the Indus Valley, in what is now Pakistan, also contained toilets flushed with clean water, as did some homes in ancient Rome. Medieval monasteries often contained flush toilets too.
A toilet using a chain to open a valve and deliver water to the bowl was already in use in England by 1775. But the kind of flush toilet we’re most familiar with was designed late in the 19th century by an Englishman named Thomas Crapper.
Crapper’s toilet was the first to employ a device that would automatically stop the water from flowing into the reservoir after it was filled. Before this, many people would leave the water flowing continually to assure cleanliness.