Before European settlers arrived, the Native American population in Somerset County was divided into seven distinct areas, one of which included Green Brook Township. In this area lived the Raritan Tribe. Prior to the early 1600's the Raritan's controlled the "Plains" between the mountains and the Raritan Bay. The layout of their trails, and the location of their villages, showed great skill in the optimal use of resources. They took into consideration the availability of water and food, the climate, the risk of storms and floods, and the proximity of the primary trails.
The area along the Green Brook favored all of these things. The brook was much larger than it is now and was a great help to them in traveling from place to place. It also furnished them with a great deal of their food. The many springs along the brook gave them their water supply. They were close to the Minnisink Trail, which went through what is now Plainfield. The mountains served as a barrier against the cold winds and many of the sandy bluffs through which the brook flows made ideal campsites.
Broken pottery, arrowheads, firestone, stone chips, stone implements, and other relics found within a few hundred feet of Sebring's Mill, mark the location of a camp, which continued along the brook to what is now the site of the Presbyterian Cemetery at Bound Brook. Farther upstream in the vicinity of Plainfield, near Grant Avenue and Clinton Avenue, there were two large encampments.
In the first Indian purchase, on May 4, 1681, mentions Metapes Wigwam, which was at the site of Sebring's Mill. All along the brook and throughout the township Indian relics have been found which definitely tell us that these people had once occupied this territory.
Mr. C. Vail, a descendant of an early Vail family of Green Brook, who was interviewed in May, 1940, had in his possession an Indian axe, which along with many other relics, was found under a huge chestnut tree growing near Green Brook Road. The tree stood about three hundred feet west of the house known as "Twin Chimney's" now owned by Mr. and Mrs. Benjamin F. Leake.
This tree measured twenty-seven feet in circumference and was very old. About 1925 it was found necessary to remove the tree, and in the process the relics were unearthed. The things were so nearly perfect that it is thought the spot may have been the grave of some great Indian chief. An Indian custom was to bury "the best" with the chief.
Mr. Vail, who lived in Plainfield at the time of the interview in 1940, was over ninety years of age. He supplied the picture of this tree that also played a part in the revolutionary War stories of Green Brook.
A few mortars and pestles found in the vicinity of Green Brook indicate the growing of cereal grains that would necessitate the use of such implements. That these Indians possessed a higher degree of civilization than many of the more savage tribes is evident.
The white settlers in this section found the Raritan Indians trustworthy, friendly, peaceful, and willing to abide by any bargains they had made concerning their lands. They were willing to share their knowledge of anything that would make the white man's life easier in the new world. Most of the settlers were Quakers who followed closely the ideals of William Penn so they lived together in "Peace".
In other settlements (not Quaker settlements) we read of trouble with the Indians but it usually started when the Indians found that they were being cheated or taken advantage of. They were quick to sense any injury done them.
Just how long the Indians remained in this section cannot be clearly ascertained. Tradition tells us of an Indian wigwam located near what is now Washington Rock about the year 1777, the time of Washington's visit there during the Revolution. Mention is made in the Somerset Historical Quarterly - Volume I - of a grand parade of Washington's Army near Bound Brook in honor of a band of Indians who had come to visit him and to whom the Commander deemed it good policy to show his attention and favor.
The white settlers were moving into the area in greater numbers. As the years went by the Indians saw the lands that had been theirs for so long being taken away. They no longer could live the life to which they had been accustomed so they left, quietly and peacefully, probably in the late 1700's. In "Carlisle and Men of Other Days" the Raritans are said to have had a village in western Pennsylvania after 1756 and no other reference to them has come to light.