The Pilgrims were persecuted in England. They wish to go to the new land. But a series of unfortunate events led them to Amsterdam away from the farms and into the big city. The Pilgrims were not persecuted there but the kids were learning city ways and they stated to fall apart since the "persecution" was the glue that held them together. So they were motivated to get that ship built in England, finally. But had only 50 Pilgrims left  now to go to the new world, the rest were non-religious. On the trip they messed up, left so they arrived in the late fall and way off course. They got on dry land and found an Indian store house to raid, said they would pay them back.  The shipmates were wise, fighting over religion killed off a lot of folks. So before they stepped on shore as a group they agreed that the new colony would be ruled under the laws of England, not of any religion. Simple, they needed all to survive an when other colonies failed, one in fact nearby, they survived.