write 1000 words about the historical background of the matter with title: "“Το Βορειοηπειρωτικό ζήτημα υπό το πρίσμα της υψηλής στρατηγικής των Μεγάλων Δυνάμεων του μεσοπολέμου” with details for this matter: ""The Northern Epirus Issue under the prism of high strategy of Great Powers during interwar period". The Great Powers were concerned with maintaining their influence in the region and preventing any one power from gaining too much control12. The Protocol of NAME_1 ceded the northern part of this area, which became known as "Northern Epirus", to Albania. This turn of events was highly unpopular among local Greeks, who decided to declare their independence and secure the region against any opposing threat"