Prior to standardization, the measurement of length designated “the foot” was a different size depending on which country or region you were in.
Notable variants included the Prussian foot, the Rijnland foot (which became the Cape foot used in South Africa), and the Chinese mathematician’s foot (which is smaller than the tradesman’s foot for some reason). The largest obsolete foot was the Bordeaux foot (35.7cm, 1’2”); the smallest was the Utrect foot (27.2cm, 10”).
Some countries (usually empires!) tried to standardise the foot within their territory: the Roman foot, the metric foot from France, and the Indian survey foot. The United States still uses the foot, but for most of the world all feet are now obsolete.