Unio Trium Nationum

Unio Trium Nationum (Latin for "Union of the Three Nations") was a pact of mutual aid codified in 1438 by three Estates of Transylvania: the (largely Hungarian) nobility, the Saxon (German) patrician class (represented by the Transylvanian Saxon University), and the free military Székelys. The union was directed against the whole of the peasantry, regardless of ethnicity, in response to the Transylvanian peasant revolt.

In this typical feudal estate parliament, the peasants (whether Hungarian, Saxon, Székely, or Romanian in origin) were not represented, and they did not benefit from its acts, as the commoners were not considered to be members of these feudal "nations".