Irredentism
Etymology
From Italian irredento, “unredeemed,” from the phrase Italia irredenta — “unredeemed Italy” — used in the late nineteenth century for Italian-speaking areas still outside the new Italian state. The image is of territory waiting to be “redeemed,” or brought home. The term generalized to any such claim, and it recurs wherever states press to absorb neighboring lands.
noun · /ir-ih-DEN-tiz-um/
A political movement to reclaim and annex territory that a state regards as rightfully its own, usually on ethnic or historical grounds.
What it names
The often-overlooked engine behind many border conflicts — a claim to land “across the line” where kindred people or a lost homeland are said to be.
Example
The map on the poster, showing borders far beyond the current ones, was a naked appeal to irredentism.
Related idea
Revanchism is driven by the wish to reverse a past defeat and avenge lost pride; irredentism focuses specifically on recovering territory, though the two often overlap.