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Salt

Vending of common salt (sodium chloride) was historically a natural monopoly. Until recently, a combination of strong sunshine and low humidity or an extension of peat marshes was necessary for producing salt from the sea, the most plentiful source. Changing sea levels periodically caused salt " famines " and communities were forced to depend upon those who controlled the scarce inland mines and salt springs, which were often in hostile areas (e.g. the Sahara) requiring well-organised security for transport, storage, and distribution.

The Salt Commission was a legal monopoly in China. Formed in 758, the commission controlled salt production and sales in order to raise tax revenue for the Tang dynasty.

The " Gabelle " was a notoriously high tax levied upon salt in the Kingdom of France. The much-hated levy had a role in the beginning of the French Revolution, when strict legal controls specified who was allowed to sell and distribute salt. First instituted in 1286, the Gabelle was not permanently abolished until 1945.