Which 1860 treaty created the first modern free-trade agreement between Britain and France?

The Cobden–Chevalier Treaty created the first modern free-trade agreement between Britain and France in 1860. It reduced or removed tariffs on many goods traded between the two countries.

The agreement was negotiated by British politician Richard Cobden and French statesman Michel Chevalier. French Emperor Napoleon III supported the move toward freer trade, while Britain’s commercial policy had already shifted away from many protectionist restrictions after the repeal of the Corn Laws in 1846.

The treaty included a most-favoured-nation clause. This meant that if either country later granted another trading partner a better tariff treatment, the same treatment would generally extend to the treaty partner. That feature helped spread tariff reductions through a network of later European trade agreements.

The treaty did not eliminate every trade barrier, and it did not create a modern customs union or single market. Its importance lies in making reciprocal tariff reduction a prominent feature of nineteenth-century commercial diplomacy.