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We analyzed a sediment core from Piseco Lake, New York (USA), to infer late Holocene environmental conditions and look for evidence of prehistoric human activity in the region. We analyzed fossil pollen, charcoal, and geochemistry in sediments deposited over the last similar to 1800 years. The pollen record indicates the area was dominated primarily by Betula (birch), Pinus (pine), and Tsuga (hemlock). Picea (spruce) increased after similar to 1560 cal yr BP and eventually became a major component of the forest. A transition in the fire regime around Piseco Lake occurred after similar to 900 cal yr BP, perhaps associated with drier conditions during the Medieval Climate Anomaly, ca. 1000-600 BP. A fire ca. 580 cal yr BP, along with decline of Tsuga after similar to 520 cal yr BP, may reflect generally dry conditions of the Little Ice Age (600-150 BP). Climate change may have swamped any evidence for low-intensity, prehistoric human activity around Piseco Lake. The rise in Poaceae (grass) and Ambrosia (ragweed) pollen similar to 130 cal yr BP indicates European settlement in the area, and is followed by rapid decline of Tsuga and Pinus, most likely a consequence of logging. Since about 145 cal yr BP, increases in macroscopic charcoal concentrations and changes in sediment geochemistry indicate increased erosion and nutrient influx to Piseco Lake, likely related to anthropogenic activities.