Abstract:One of the key events in the relations between the Athenians and Thebans was the Plataian decision to align themselves with the Athenians at the end of the sixth century BCE.This decision shook up the contemporary political landscape and proved to be a source of hostility between the two neighbouring polities throughout the fifth and fourth centuries. The orthodox view holds that the original alignment took place in 519 during the Peisistratid tyranny, based on the date given by Thucydides 3.68.5. This date, in the mind of some scholars, seems contradictory with the story of the Plataian alignment as given by Herodotus (6.108.1-6.). This inconsistency resulted in a search for alternatives that fit the Herodotean narrative better. To accommodate this change, they relied on emendating the Thucydidean text, but there is no sign of corruption in this part. Emendation of a text is best avoided, although the controversy merits attention. Therefore, in this article it will be argued that the two narratives -the Thucydidean and the Herodotean -need to be separated. What follows is a renewed chronology of PlataianAthenian relations. The orthodox date (519) was the date of an original Peisistratid-Plataian alliance that did not lead to hostilities with Thebes. Instead, it is in the context of the foundation of the Athenian democracy and the subsequent clashes with Thebes after 507/6 that the Herodotean narrative should be placed.* First and foremost I would like express my gratitude to Albert Schachter, who made invaluable suggestions to improve this article. Another note goes out to Fabienne Marchand, who pointed to numerous mistakes in the article. A further acknowledgement is to professor Nikolaos Papazarkadas, who suggested the similarities between sympoliteia and the Eleutherai inscription mentioned later on. I would also to thank the audience at Durham, where an earlier version of this paper has been given, for their comments. A last note of gratitude goes to the anonymous reviewer, whose advice radically improved this article. Finally, I would like to thank the Swiss National Science Foundation for generously supporting me to carry out research on Athenian-Boiotian relations.