A、Because it was more nutritious than other type of bread. B、Because it did not require yeast. C、Because it stayed fresh for a l

During the early American colonial years, corn was more plentiful than wheat, so corn bread was more common than wheat bread. Friendly Indians showed colonists how to grow corn and how to prepare it for food and pioneer women then improved the Indian cooking techniques. When people traveled, they went on foot or horseback, sleeping and eating in the forests. They carried corn bread for sustenance. The corn bread came to be called journeyeake. Later when roads and taverns were built and stagecoaches carried passengers, journeycake became johnnycake, a name many easterners still use for corn bread. The kinds of bread made with cornmeal were  and still are  almost without limit. Every region has its specialties.
    From the start, southerners showed a preference for white eorm:neal, northerners for yellow. And pioneers on the frontier, when they ran out of yeast, made salt-rising bread. They stirred together water, a little water ground cornmeal, potatoes, and salt. They set the mixture, uncovered, in a warm place until it absorbed bacteria from the air and began to ferment. Then they removed the potatoes and used the liquid as leavening for their bread, made with white flour.