Prominent irredentist disputes during the past century have included:
Europe
Spanish claims to Gibraltar which was ceded in perpetuity to Britain in 1713 under the Treaty of Utrecht, and argues its case at the United Nations claiming its territorial integrity is affected.
Greece's claims on areas of the ex-Ottoman Empire. After World War I Greece claimed what is now the Aegean coastline of Turkey, because of the predominance there of Greek population since antiquity and former rule by the Byzantine Empire. Other Greek irredentist claims under the "Greater Greece" policy called Megali Idea included south Albania (Northern Epirus) and Cyprus.
Hungarian claims to parts of the neighbouring countries inhabited by the ethnic Hungarians (including parts of Slovakia, Romania, Serbia, Ukraine, etc.). The claim is based on historic criteria for some regions (such as Transylvania, where Hungarians are a minority in two counties), and ethnic for other regions. Hungary actually lost 2/3 of territories according to the treaty of Trianon in 1920.
Albanian claims to Kosovo, which Serbia asserts is a province of Serbia, and which the Kosovar government insists is an independent country, as well as to parts of the Montenegro, the Republic of Macedonia (on grounds of ethnic affiliation) and Greece.
Irredentists from the Republic of Macedonia have expressed land claims to the entire region of Macedonia out of which only 40% lies within the Republic of Macedonia, the rest being in Greece, Bulgaria and Albania, on the purported grounds of ethnic affiliation.
Bulgarian irredentists have claimed the Republic of Macedonia based on the idea that the Macedonians are actually Bulgarians, this was an important factor in Bulgarian foreign policy between Bulgarian independence and World War II.
Cambodia has claimed parts of the Mekong Delta that lie in present day Vietnam on the basis that the area, which was formerly part of the Khmer Empire, was artificially carved up by the French during the Colonial Period and given to South Vietnam upon French withdrawal. The area still is home to at least one million ethnic Khmers (the Khmer Krom) who claim to be persecuted by the Vietnamese.
South America
Bolivian claims to coastal regions of Chile annexed after the War of the Pacific. More recently, president Evo Morales has expressed his disgust with the secession of Acre (1902), which later become a Brazilian state, saying that the Brazilians provoked the unrest and later paid Bolvia only "a horse's price" for the priceless land.[3]
The following is an incomplete list of irredentist entities, both present and historical (i.e. non-extant). Note that "Greater" does not necessarily denote irredentism, but as in the case of Greater India or Greater Middle East may simply refer to historical socio-cultural regions.