AEK Athens FC was founded on 13 April 1924 by Greek refugees from Constantinople, forced to leave the city following the Greco-Turkish War and the subsequent population exchange between Greece and Turkey. The club was established by more than forty members of the Athenian community with Constantinopolitan roots, and its first president was journalist and politician Konstantinos Spanoudis. That lost homeland remains central to the club's identity: the yellow-and-blacks are represented by the Byzantine Double-Headed Eagle, drawn from the imperial emblem of the Byzantine Empire, whose capital was Constantinople itself.
A defining moment in the club's pre-war history came in the 1939 season, when AEK became the first club in the history of Greek football to complete the domestic double, winning both the league title and the Greek Cup in the same year, before retaining the championship the following season. The club's golden age, however, came in the 1960s and 1970s, when a legendary attacking duo — five-time consecutive league top scorer Kostas Nestoridis and Mimis Papaioannou, who despite interest from Real Madrid remained loyal to the club for 18 seasons — led AEK to further championship titles.
Domestically, AEK have won 14 Greek league championships and 16 Greek Cups, standing alongside Olympiacos and Panathinaikos as one of the three clubs that have long dominated Greek football. On the European stage, the club made history in the 1968–69 season by becoming the first Greek team to reach the quarter-finals of the European Cup. Eight years later, in 1976–77, AEK advanced to the semi-finals of the UEFA Cup — still one of the finest European campaigns in Greek club football history.
The team's current home is the Agia Sophia Stadium, opened in 2022 in the Nea Filadelphia district, on the site of the earlier Nikos Goumas Stadium, which had stood there since 1930. Regardless of any commercial sponsorship name attached to it over the years, the ground's name deliberately recalls the historic Hagia Sophia cathedral of Constantinople, the foremost church of Eastern Christianity and a symbol of the homeland the club's founders lost. The stadium's design draws on the walls of Constantinople, and it also houses a museum dedicated to the Greek refugees of Asia Minor.