Space Viking by H. Beam Piper

Attempting to conceal the presence on Tanith of Prince Bentrik's wife and son was pushing caution beyond necessity. Admitted that the news would leak back to Marduk via Gilgamesh, it was over seven hundred light-years to the latter and almost a thousand from there to the former. Better that Princess Lucile should enjoy Rivington society, such as it was, and escape, for a moment now and then, from anxiety about her husband. At ten -- no, almost twelve; it had been a year and a half since Trask had left Marduk -- the boy Count of Ravary was more easily diverted. At last, he was among real Space Vikings, on a Space Viking planet, and he was trying to be everywhere and see everything at once. No doubt he would be imagining himself a Space Viking, returning to Marduk with a vast armada to rescue his father and the King from Zaspar Makann.

Trask was satisfied with that; as a host he left much to be desired. He had his worries, too, and all of them bore the same name: Prince Viktor of Xochitl. He went over with Manfred Ravallo everything the captain of the _Black Star_ could tell him. He had talked once with Viktor; the lord of Xochitl had been coldly polite and noncommittal. His subordinates had been frankly hostile. There had been five ships on orbit or landed at Viktor's spaceport beside the usual Gilgameshers and itinerant traders, two of them Viktor's own, and a big armed freighter had come in from Haulteclere as the _Black Star_ was leaving. There was considerable activity at the shipyards and around the spaceport, as though in preparation for something on a large scale.