Who invented the toilet and when?

16th-century author Sir John Harrington. Harrington was an author and in 1596, he wrote an article named "Plan Plots of a Privy of Perfection." In this article, he described his idea of a flush toilet. Queen Elizabeth I was so impressed by his idea that she asked Harrington to install one in the Royal Palace.

The first patent for a flush toilet was issued to Alexander Cummings, a watchmaker in 1775.