Ocean of Grass: Petrellan Saga 1 - Petrellan Saga, #1

Beached on an unforgiving shore, her beloved Sea Eagle destroyed by the Priest-Admiral's fleet, Sarasha must overcome her crippling injury to lead her people to a new, free life on the Great Prairie. But strong leadership creates dependence, and dependence leads to tyranny, and the whole vicious cycle will start over again. The beginning of the Petrellan Saga, the story of a people and the forces that caused them to migrate over 400 years from a freezing ocean to a prairie to a rich land beyond the mountains.
This book chronicles the original rebellion against tyranny that began the trek.