The Seneca people used the lake and its surrounding area for hunting and fishing near the south end of the lake up until the late 1770s. In September 1779 General John Sullivan and his army drove the natives away from the lake as part of the Sullivan Expedition.
In the 1790s Hemlock Lake received its first white settlers. Most of these settlers were involved in the lumber industry and built their homes out of wooden slabs by the outlet which is located at the north end of the lake. For a time, this place was known as “Slab City”. The lake was used to float logs to Slab City in the summer months as well as to haul logs on the ice in the winter time.
