Ἱππίης μὲν δὴ ταύτῃ τὴν ὄψιν συνεβάλετο ἐξεληλυθέναι. Ἀθηναίοισι δὲ τεταγμένοισι ἐν τεμένεϊ Ἡρακλέος ἐπῆλθον βοηθέοντες Πλαταιέες πανδημεί. καὶ γὰρ καὶ ἐδεδώκεσαν σφέας αὐτοὺς τοῖσι Ἀθηναίοισι οἱ Πλαταιέες, καὶ πόνους ὑπὲρ αὐτῶν οἱ Ἀθηναῖοι συχνοὺς ἤδη ἀναραιρέατο: ἔδοσαν δὲ ὧδε.  πιεζεύμενοι ὑπὸ Θηβαίων οἱ Πλαταιέες ἐδίδοσαν πρῶτα παρατυχοῦσι Κλεομένεΐ τε τῷ Ἀναξανδρίδεω καὶ Λακεδαιμονίοισι σφέας αὐτούς. οἳ δὲ οὐ δεκόμενοι ἔλεγόν σφι τάδε. ‘ἡμεῖς μὲν ἑκαστέρω τε οἰκέομεν, καὶ ὑμῖν τοιήδε τις γίνοιτ᾽ ἂν ἐπικουρίη ψυχρή: φθαίητε γὰρ ἂν πολλάκις ἐξανδραποδισθέντες ἤ τινα πυθέσθαι ἡμέων.  συμβουλεύομεν δὲ ὑμῖν δοῦναι ὑμέας αὐτοὺς Ἀθηναίοισι, πλησιοχώροισι τε ἀνδράσι καὶ τιμωρέειν ἐοῦσι οὐ κακοῖσι.’ ταῦτα συνεβούλευον οἱ Λακεδαιμόνιοι οὐ κατὰ τὴν εὐνοίην οὕτω τῶν Πλαταιέων ὡς βουλόμενοι τοὺς Ἀθηναίους ἔχειν πόνους συνεστεῶτας Βοιωτοῖσι.  Λακεδαιμόνιοι μέν νυν Πλαταιεῦσι ταῦτα συνεβούλευον, οἳ δὲ οὐκ ἠπίστησαν, ἀλλ᾽ Ἀθηναίων ἱρὰ ποιεύντων τοῖσι δυώδεκα θεοῖσι ἱκέται ἱζόμενοι ἐπὶ τὸν βωμὸν ἐδίδοσαν σφέας αὐτούς. Θηβαῖοι δὲ πυθόμενοι ταῦτα ἐστρατεύοντο ἐπὶ τοὺς Πλαταιέας, Ἀθηναῖοι δέ σφι ἐβοήθεον.  μελλόντων δὲ συνάπτειν μάχην Κορίνθιοι οὐ περιεῖδον, παρατυχόντες δὲ καὶ καταλλάξαντες ἐπιτρεψάντων ἀμφοτέρων οὔρισαν τὴν χώρην ἐπὶ τοῖσιδε, ἐᾶν Θηβαίους Βοιωτῶν τοὺς μὴ βουλομένους ἐς Βοιωτοὺς τελέειν. Κορίνθιοι μὲν δὴ ταῦτα γνόντες ἀπαλλάσσοντο, Ἀθηναίοισι δὲ ἀπιοῦσι ἐπεθήκαντο Βοιωτοί, ἐπιθέμενοι δὲ ἑσσώθησαν τῇ μάχῃ.  ὑπερβάντες δὲ οἱ Ἀθηναῖοι τοὺς οἱ Κορίνθιοι ἔθηκαν Πλαταιεῦσι εἶναι οὔρους, τούτους ὑπερβάντες τὸν Ἀσωπὸν αὐτὸν ἐποιήσαντο οὖρον Θηβαίοισι πρὸς Πλαταιέας εἶναι καὶ Ὑσιάς. ἔδοσαν μὲν δὴ οἱ Πλαταιέες σφέας αὐτοὺς Ἀθηναίοισι τρόπῳ τῷ εἰρημένῳ, ἧκον δὲ τότε ἐς Μαραθῶνα βοηθέοντες.
Hippias understood that his vision had been fulfilled like this. But the Plataeans came in full force to support the Athenians who were drawn up in the precinct of Heracles. Of course they did, for the Athenians were already undertaking many initiatives on their behalf. It was thus that they rendered this help. (2) While under pressure from the Thebans, the Plataeans first committed themselves to Cleomenes the son of Anaxandridas and the Spartans who were there; but they did not accept them and said this to them: ‘We live too far away, and some such support would be lukewarm for you. You would be reduced to slavery many times before any of us knew. (3) We advise you to commit yourselves to the Athenians – men who are nearer at hand and are not bad in giving support.’ This is what the Spartans advised, not so much for good will for the Plataeans as wanting the Athenians to have problems since they had been put in conflict with the Boeotians. (4) The Spartans gave this advice to the Plataeans, and they followed it completely; but when the Athenians were making offerings to the twelve gods at the altar, they surrendered themselves to them. But when the Thebans found this out, they marched against the Plataeans, but the Athenians supported them. (5) When they were about to join battle, the Corinthians did not overlook it, but as they happened to be present, when both parties turned to them, they reconciled them and marked out the territory on both sides on the following terms: that the Thebans would leave alone those of the Boeotians who did not want to belong to the Thebans. The Corinthians for their part gave this judgement and went off, but the Boeotians for their part attacked the Athenians as they were departing. But when they attacked, they were defeated in the battle. (6) The Athenians crossed the boundaries which the Corinthians had caused to be in place, and having crossed these, they made the Asopus itself to be the boundary for the Thebans towards Plataea and Hysiae. The Plataeans did indeed commit themselves to the Athenians in the way that I have said, and for their part they then came to Marathon to support.