evidence: Olivenza is a town near the border of Portugal and Spain. Spain controls it but Portugal does not recognize it as Spanish. Unlike other disputes around the world such as Gibraltar in Spain vs UK, it does not seem to be brought up nor does it sour relations between the two countries. Why is this? Is it because it is of less significance than others due to both countries being in Schengen, EU and NATO? [...] The issue is several centuries old. No living people, not even their grandfathers, were born in Portuguese Olivenza. [...] There is basically no claim of Portugal based on nationality of Olivenza citizens. According to wikipedia "In the beginning of 2018, the number of residents with Portuguese nationality is around 800 (6% of the town's population)".