The Bretwaldate of Vinland is a fictional nation which serves as the primary setting of the short story "The Wheels of If" (1940), by L. Sprague de Camp. Vinland exists in a timeline which diverged from OTL in 664. It is a geographic analog of much of the northeastern United States and southern Canada, with its capital in New Belfast, a geographic analog of New York. Its people are primarily the descendants of medieval Vikings and Irish people. Allister Park, a New York lawyer from OTL, is accidentally transported across time to the Vinland timeline, where he inhabits the body of New Belfast aristocrat Ib Scoglund (a Bishop of the Celtic Christian Church), who is his "analog" for that timeline. Park and Scoglund, who merge into one being over the course of the story, continue Scoglund's work of advocating for the civil rights of the indigenous Skrellings. Park travels with Vinland's army as a political consultant, to the front in a border war with both a neighboring nation (Dakotia) and a racialist insurrection from within. He concocts a clever scheme of espionage and trickery, which defeats both antagonists and saves Vinland's sovereignty.
Bretwaldate of Vinland in "The Pugnacious Peacemaker"
The Bretwaldate of Vinland of Ib Scoglund's timeline did not have the international weight of the United States of Allister Park's native world. Nevertheless, it had a reasonably good standing on the International Court for the Continent of Skrelleland. For that reason, Scoglund, as a Vinlander judge for the court, was chosen to travel to South Skrelleland to attempt to end the vicious cycle of wars between the Empire of Tawantiinsuuju and the Emirate of the dar al-Harb.