According to the official history of the club, Panathinaikos was founded by Giorgos Kalafatis on 3 February 1908, when he and 40 other athletes decided to break away from Panellinios Gymnastikos Syllogos following the club's decision to discontinue its football team. The first name of the new club was Podosferikos Omilos Athinon (POA), the colours of the team were red and white and its home ground was in Patission Street. Oxford University athlete John Cyril Campbell was brought in as coach. It was the first time that a foreigner was appointed as the coach of a Greek team.
Panellinios Podosferikos Omilos
In 1910, after a dispute among a number of board members, Kalafatis with most of the players - also followed by Campbell - decided to pull out of POA and secured a new ground in Amerikis Square. Subsequently, the name of the club changed to Panellinios Podosferikos Omilos (PPO) and its colours to green and white. By 1914, Campbell had returned to England but the club was already at the top of Greek football with players such as Michalis Papazoglou, Michalis Rokkos and Loukas Panourgias.
In 1918, PPO adopted the shamrock as its emblem, as proposed by Michalis Papazoglou. In 1921 and 1922, the Athens-Piraeus FCA organized the first two post-WWI championships, in both of which PPO was declared champion. By that stage, the club had outgrown both the grounds in Patission Street and Amerikis Square, due mainly to its expansion in other sports, and began to look at vacant land in the area of Perivola on Alexandras Avenue as its potential new ground. After long discussions with the Municipality of Athens, an agreement was finally reached and in 1922 Leoforos ("Avenue" in Greek) was granted to the