The EBTs a number of times (eg. AN 7.62) depict the Buddha speaking of his past lives as a universal monarch:
Many hundreds of times I was a king, a wheel-turning monarch, a just and principled king. My dominion extended to all four sides, I achieved stability in the country, and I possessed the seven treasures.
The Itivuttaka (Iti 22) appends to the stock description the phrase:
Ko pana vādo padesarajjassa.
Let alone local kingship.
The phrase is not a problematic one. But curiously enough the notion of “local” king—i.e. the king of a specific nation, such as, presumably, one of the 16 janapadas extant at the time of the Buddha—does not appear in the early strata of the texts. It makes an appearance through a range of texts considered to be somewhat later.
The Itivuttaka is one such text. Padesarāja also appears in the Vinaya (Pj 2), Milinda (Mil 5.4.7, Mil 6.2.4), the Netti (Ne 37), the Khuddakapatha (Kp 8), and frequently in the Apadānas.
The emergence of the term possibly relates to the changing political situation. In the time of the Buddha, all kings were “local”, and the universal monarch was spoken of solely in mythic terms. But a century or so later, the Magadhan kingdom had grown to cover virtually all of the India that the Buddha knew, and soon after, much further. It would seem natural that in such a state, when the “king” was in fact a world-spanning emperor, that the more humble local kings of an earlier day were distinguished with a specific title.
I don’t personally think of the Itivuttaka as a particularly late text. I think it was probably compiled during the same period as the main nikayas, although perhaps fixed in form towards the end of that period. But this one word, although hardly significant by itself, perhaps hints at an affinity with the later canon rather than the early.