Is Σαδυάττεω the dative of Σαδυάττης?

Hdt. 1.16.1

Ἄρδυος δὲ βασιλεύσαντος ἑνὸς δέοντα πεντήκοντα ἔτεα ἐξεδέξατο Σαδυάττης ὁ Ἄρδυος, καὶ ἐβασίλευσε ἔτεα δυώδεκα, Σαδυάττεω δὲ Ἀλυάττης

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What declension is Σαδυάττης? It looks like a masculine first declension but could it be a third declension?

The context seems to require after Σαδυάττης ὁ Ἄρδυος, "And he ruled 12 years, and from-Saduattes Alyattes (succeded). Some for of dative seems most likely to provide that sense but I’m guessing.

I’d say genitive, since in Attic it would be Σαδυάττου

Ionic πολίτης is πολίτεω in the genitive. You can see Smyth 214 D. 5. b.

Thank you both.
Interestingly, last night, just as I was drifting off into sleep, it occurred to me that the genitive was more likely as it is associated with coming from. Thanks for the confirmation.

After a year of Greek you can read Mark without a dictionary and find your way round Smyth? :astonished:

My acquaintance with Smyth has only just begun. But on that note, I recommend checking this Perseus release: https://github.com/PerseusDL/sg_reader

It is in early stages, but if you clone that repository you will find that it includes all of Smyth in easy-to-use (and search!) html files.