The Town of Wallkill was established April 7, 1772, at the home of Samuel Watkins in Campbell Hall in the present Town of Hamptonburgh. Vast tracts of wilderness, called patents, were acquired from the Indians over the period from 1703 to 1761. The original Wallkill Precinct was created from portions of two of these patents, the Minisink Angle and the John Evens Patent.

Wallkill Precinct originally extended into Ulster County and was much larger than its present day boundaries. In 1798, by an act of the Legislature, the present Orange-Ulster County boundaries were formed.

In the early 1960's the Town of Wallkill began to feel the impact of development as new highways put it within driving distance of New York City and New Jersey. The opening of Routes 17 and 84 and the placement of interchanges in the Town changed the complexion of the area. In 1960, the census reported 8000, and in 1980 the census showed the population grew to 20,481. By 1987, it had grown to approximately 27,000.