Archeological evidence suggests that humans have lived in the area that is now New Jersey for thousands of years.  The most prominent Native American tribe in New Jersey was the Lenape, or Delaware (Delaware Tribe of Indians Homepage).  A survey conducted between 1912 and 1915 identified four hundred and sixty-two camps, villages, burial sites, and rock shelters within Hunterdon County (Hunterdon County Democrat 1976, p. 4).  The majority of sites within Union that contain Native American artifacts currently lie under the Spruce Run Reservoir.  An early Native American trail followed Mulhockaway Creek from West Portal, through Union Township, and up to High Bridge.  Another trail, called Malayelick Path, originated in the village of Assunpink (Trenton), and apparently crossed through Union Township’s southern border (Union Township Historical Society 1976; Hunterdon County Democrat 1976, pp. 4-6). 

Hunterdon County provided rich hunting grounds to the Lenape, for most of the county was densely forested.  Hunterdon County also provided the Lenape with argillite, a hard rock formation used by to make various tools and weapons.  Because of its abundance, Native American tribes traveled from as far away as Port Jervis, New York, to acquire Argillite (Union Township Historical Society 1976; Herdan 1987).

The Lenape and the Delaware were among the first Native Americans to come in contact with the European settlers who arrived in Hunterdon County in the early 1700s.  At the turn of the 19th century, colonial settlements had become larger in size and number, which changed the political and social life of the Lenape.  The Lenape eventually were forced to relocate to Oklahoma (Hunterdon County Democrat 1976, pp. 4-6; Herdan 1987).