One King's Way

Description for ONE KING'S WAY by Harry Harrison:

WHAT IF... THE VIKINGS CONQUERED BRITAIN -- AND THREATENED THE ENTIRE CHRISTIAN WORLD?

A craftsman, visionary, and warrior, Shef has risen from slavery to become king of a mighty Viking nation. But his growing kingdom menaces all of Europe, and he has made many powerful enemies.

Chief among his enemies are the Knights of the Lance, a fanatical order of soldiers sworn to bring Shef down, no matter what the cost. To defeat Shef, they will go to extraordinary lengths to find the sacred spear of Christ--and resurrect the Holy Roman Empire.

Driven by dreams, Shef battles to change the course of history, but even the gods themselves may be plotting against him....