Irredentism is claiming a right to territories belonging to another state on the grounds of prior historical possession, actual or alleged. The word was coined in Italy from the phrase terra irredenta, meaning "unredeemed land". This originally referred to Austro-Hungarian rule over Italian-inhabited territories in the northern Adriatic during the 19th and early 20th century. An area subjected to an irredentist claim is sometimes called an irredenta.

Irredentist disputes

Not all territorial disputes are irredentist, although they are often couched in irredentist terms to strengthen public support.

Prominent irredentist disputes have included: