Limitrophe states

Limitrophe states are territories situated on a border or frontier. In a broad sense, it means border countries, any group of neighbors of a given nation which border one another thus forming a rim around that country. The English term derives from pays limitrophes, a term in diplomatic French.

In ancient Rome, the term referred to provinces at the borders of the Roman Empire (Latin: limitrophus), which were obliged to provide billeting of the limitanei legions deployed on their territory, mostly in limes.

In modern history, it was used to refer to provinces that seceded from the Russian Empire at the end of World War I, during the Russian Civil War (1917–1922), thus forming a kind of belt or cordon sanitaire separating Soviet Russia from the rest of Europe during the interwar period.