“Understand well,” Engus went on, “that I am sole king of this land, and that while your kind live here, you will obey the laws of the Folk. I care not what gods you worship, what rituals you observe; that is your own choice, though no doubt Brother Tadhg here will try to change your ways. He works daily on our own recalcitrant minds to little avail. I offer a single warning, but one which must never be forgotten. These islands are full of ancient powers. You have seen the place of standing stones. These markers hold together the very fabric of the Light Isles. They are far older than the Folk; they were set there by hands whose bones were the very bones of the earth herself. There are other such places, other such signs. Interfere with them at your peril.”

“I understand,” said Ulf. “The stones are indeed wondrous. A man would be a fool not to recognize their importance.”

Engus nodded. “Then we are friends and allies from this day onward. Let this treaty be sworn with due ceremony in three days time. We shall meet at the Great Stone of Oaths, and there make our vow of peace and friendship under the eyes of the ancestors. Let all men here be present at that time.”

“In our homeland,” commented Ulf’s adviser, Olaf Sveinsson, with a frown, “such an oath must be ring-sworn; only then is it truly binding. A fine circle of gold, sacred to Odin or to Thor, allows the gods themselves to bear witness to the solemnity of such a promise.”

“A ring?” queried Engus. “If that is your custom, what I propose should satisfy you well. The place of our ritual will permit this vow to be doubly sacred, and doubly strong. When we meet for the swearing you will understand my meaning.”

Even so was it done. Nessa had the account of it from Kinart, for this oath was between men, and even the priestess of the Folk did not attend at such a swearing. Her cousin told her how, at the appointed time, the men of the islands had gathered around the sacred stone, which stood majestically alone in the fields close by the place of the greater and lesser circles, in that part of the land where lake shone under sky, where cloud lay drowned in water, where wind whistled around the ancient monoliths and sang across the buried chambers. In this place, margins met and blurred; the elements merged, and the ancestors whispered in the ear of any true son of the Folk. A vow made here, on the Great Stone of Oaths, was as binding as any promise might be. No man dared break such an oath.