Following the war, many of the clubs players retired and were replaced with new, important players such as Mouratis, Chatzistaviridis and Kourouklatos. Other stars of the team included  Captain and prolific goal scorer Giannis Vazos remained at Olympiakos, and so did Giannis Chelmis. As soon as the league recommenced, the club returned to their dominance of Greek football. Between 1946 and 1949, Olympiakos won 9 out of 11 Greek Championships. This includes six straight, a feat unmatched in Greek football history until Olympiakos broke it themselves with seven straight championships 44 years later.

During the same period, they won over half of the Greek Cups on offer, with 8 and completed 6 doubles – 1947, 1951, 1954, 1956, 1957, 1958 and 1959. The Olympiakos team of the 1950’s became legendary, and their popularity skyrocketed even further, not just throughout Greece but all over the world, and in this era they consolidated their nickname “Thylos” (The Legend). The clubs debut on the European stage occurred on the 13th September 1959 in the 1959-60 European Cup, the first Greek team to compete in Europe. Their first game was against AC Milan and held at Karaiskasis Stadium in Piraeus. Olympiakos took the lead with a strike from Kostas Papazoglou which was the first ever goal scored by a Greek player in European competition.

Milans dangerous goalscorer Jose Altafini equalised with a well placed header in the 33rd minute, and Iilias Yfantis put Olympiakos up again with an excellent hit. Altafini scored again from a Nils Liedholm free kick to tie the game up at 2-2. Olympiakos were proud of the result, since they had no foreign players in their roster while Milan had world-class foreign players the likes of Liedholm, Altafini, Schiaffino and Grillo, as well as Cesare Maldini. Unfortunately for the Piraeus club, Milan were victors in the second leg, and Olympiakos were out. However, the clubs future history would prove to be just as eventful. 

Achievements: Greek Football Championship – Champions x9
                              Greek Cup – Winners x8
                               Piraeus FCA Championship – Champions x13

Star player: Andreas Mouratis, nickname: The Lion

Nicknamed Mouratis the Lion by the Turkish press due to his aggressive playing style, Mouratis was a burly man and an indimidating figure on the pitch for Olympiakos. In the post-war era, he led the club to numerous league and cup titles. A passionate player, he also participated in the 1952 Olympics and represented Greece 13 times.