Why did many nationalists in both Greece and North Macedonia oppose the Prespa Agreement?

The Prespa Agreement, signed in 2018 to resolve the long-standing "name issue" between Greece and the Republic of Macedonia, faced intense opposition from nationalists in both countries who viewed the compromise as a betrayal of their respective national identities and heritage.12

Opposition in North Macedonia
Macedonian nationalists largely viewed the agreement as a national disaster. They strongly opposed the mandatory change of the country’s constitutional name to the Republic of North Macedonia, viewing it as an unacceptable concession that undermined their sovereignty and national identity.12

Opposition in Greece
Greek nationalists were equally hostile, with some even calling for the execution of the politicians involved, labeling the agreement as treason. Their opposition was rooted in the belief that the term "Macedonia" and the legacy of Alexander the Great and the ancient Macedonians were the exclusive cultural and historical heritage of Greece. They rejected any recognition of a Slavic-majority state using the name "Macedonia," fearing it implied a claim to Greek history and territory.12

Both sides engaged in violent protests, reflecting the deep-seated cultural and historical tensions that had defined the Macedonian Question for decades.12