Passage 4.6.5
οὗτος δὲ ὁ Θεόπομπος· ἦν καὶ ὁ πέρας ἐπιθεὶς τῷ πολέμῳ· μαρτυρεῖ δέ μοι καὶ τὰ ἐλεγεῖα τῶν Τυρταίου λέγοντα ἡμετέρῳ βασιλῆι θεοῖσι φίλῳ Θεοπόμπῳ, ὃν διὰ Μεσσήνην εἵλομεν εὐρύχορον. Tyrtaeus, unknown location. ὁ τοίνυν Ἀριστομένης δόξῃ γε ἐμῇ γέγονεν ἐπὶ τοῦ πολέμου τοῦ ὑστέρου· καὶ τὰ ἐς αὐτόν, ἐπειδὰν ἐς τοῦτο ὁ λόγος ἀφίκηται, τηνικαῦτα ἐπέξειμι.
This Theopompus was also the one who brought the war to its conclusion. My assertion is supported by Tyrtaeus' elegiac verses, which say: "to our king dear to the gods, Theopompus, whom we seized wide-rich Messene." Aristomenes, in my opinion at least, belongs to the later war; I shall deal with what concerns him at the appropriate place in my narrative.