What is the theme in Mayflower by Nathaniel Philbrick?

Humanity is the main theme in the story. Philbrick points out several times in Mayflower that the story of the Pilgrims is one that does not fit our notions of what happened. The story is not as simple as the Pilgrims symbolizing all that is good about America or the English unleashing disease and destruction on the Native Americans or savage Indians attacking the innocent English. In fact, none of these scenes tells the whole truth, which is that both the English and the Native Americans were human. They were, at the same time, full of goodness, greed, anger, uncertainty, and a host of other conflicting behaviors.