How did salt shape trade, taxes and empires?

Salt was needed by people and animals and used to preserve food, so it became a dependable source of revenue and a prize worth controlling. Governments monopolized it or taxed it, merchants built routes to move it, and in several cases it served as money. Historians of the subject argue that the history of salt cannot be separated from the histories of commerce, medicine and taxation. [1] [2]

A PBS history programme says China built the first state-controlled salt monopoly in 700 BCE. It says historians believe salt revenue helped pay for the Great Wall and for troops defending against nomadic groups, and that between the third and fifth centuries salt made up 80 to 90 percent of state revenue in some Chinese kingdoms. The same source says the Chinese salt monopoly ended only in 2017. [3]

Salt also worked as currency. The PBS programme describes salt bars called amoles used as payment in the Empire of Aksum, a practice said to last into the early twentieth century, and it reports Marco Polo's remark that people in mountainous Yunnan used salt instead of the Great Khan's paper money. It also says Roman soldiers received part of their pay in salt, giving the word salary. That derivation is repeated in a food studies text, though the exact nature of the payment is simplified in popular tellings. [3] [4]

Salt roads spread across continents for thousands of years. The food studies text says Roman roads were built over earlier routes that archaeologists think were first used in the salt trade, and the PBS programme notes that the Via Salaria was among the busiest Roman roads. In medieval northern Germany, salt from Lüneburg travelled the Old Salt Road to Lübeck for export to Scandinavia, where salted fish created demand. The text links the wealth of this route to the founding of the Hanseatic League. [4] [3]

Venice offers another case. In the 13th century the city attributed its success to salt exports. According to Mark Kurlansky, salt made up nearly half of Venetian imports between the 14th and 16th centuries. The republic resold salt at a profit, restricted supply to hold prices up, and shut down salt works in Crete to protect its monopoly. [5]

France introduced a salt tax as early as the 13th century. It varied by region, and smuggling across regional borders became a capital offense. Richelieu reportedly compared its value to Spain's American silver mines. In the United States a salt import tax was imposed in 1797, reimposed in 1814 as a war tax, and abolished in 1894. During the Civil War the Union blockaded Southern ports and destroyed coastal saltworks, and by 1863 salt in the South cost more than 50 times its prewar price. [5]

In the Age of Exploration, sunny countries such as France, Spain and Portugal could make salt by solar evaporation and salt their catch aboard ship, giving them an advantage over cloudier England. Under the British Empire, a salt tax and a ban on Indians gathering salt in Gujarat and Orissa led to Gandhi's 1930 march to the sea, which started with 78 followers and grew to several thousand. A year later an agreement let people living on the coast make salt for their own use, though the salt tax itself lasted until the end of British rule, and the episode is described as the start of the national independence movement. One article on the British Empire also links colonial salt shortages to thoughts of rebellion in the American colonies. [4] [5] [6]