ἄρα is used in Homer much more freely than in Attic, and often so as to defy exact translation. In general ἄρα in Epic marks immediate connection and succession, a natural consequence of something already said or done; gives an explanation of an antecedent statement; or is used in recapitulations and transitions. Thus,
αὐτὰρ ἐπεί ἤγερθεν . . ., βῆ ἴμεν εἰς ἀγορήν
ὣς ἄρ' ἐφώνησεν καὶ ἀπὸ ἕο τόξον ἔθηκεν
ἐρωτήσης δὲ αὐτὸν τῆς μητρὸς . . . ἀπεκρί_νατο ἄρα ὁ Κῦρος
Herbert Weir Smyth [n.d.], A Greek Grammar for Colleges; Machine readable text [info] [word count] [Smyth].