Historical maps were also scanned and formatted to fit the document.  Other Geographic Information Systems (GIS) generated maps were created to illustrate spatial relationships between tribes, locations of villages or events, Indian trails and migration patterns, general locations of archeological finds and changes in occupancy over time. Full-page maps are offered whenever possible to provide the greatest detail over a large area.  Earlier maps of New England, done by Europeans, create the earliest geographic context New England Mass Bay Colony and Essex County.