Hi jacanterbury, thanks for providing the clue. I haven't heard the phrase used in that context before, only the governance of a country, (and it doesn't appear in Chambers under ship or state) but online Collins and Merriam- Webster give: a state/country or ...
so that justifies "rather grandly" (it's not that interesting to backtrack Plato and earlier, Longfellow etc which I imagine you've already done).
Just a cryptic definition with no wordplay to confirm is my take.