The Monetary Convention of 23 December 1865 was a unified system of coinage that provided a degree of monetary integration among several European countries, initially Belgium, France, Italy and Switzerland, at a time when the circulation of banknotes in these countries remained relatively marginal. In early 1866, it started being referred to in the British press as the Latin Monetary Union, with intent to make clear that the United Kingdom would not join,[1]: 18 and has been generally referred to under that name (French: union latine) and the acronym LMU since then. A number of countries minted coins according to the LMU standard even though they did not formally join the LMU.
The LMU has been viewed as a forerunner of late-20th-century European monetary union but cannot be directly compared with it, not least since the LMU did not rely on any common institutions.[1]: 17 Unlike the Scandinavian Monetary Union established a few years later, the Latin Monetary Union remained limited to coinage and never extended to paper money. That made the LMU increasingly less relevant, and it was quietly disbanded in 1926.[1]: 19