Using a historical record of bird specimens, we examined the effect of historical urban environments on parasitic interactions by measuring the abundance of ectoparasites on two bird species: House Finch and Hairy Woodpecker. We counted adult chewing lice and their nits from museum study skins of these two species, which were collected in the western United States from 1900 to 1932. Our urbanness metric for each specimen’s collection site and year was extracted from the Built-Up Footprint Area dataset, which measures the area covered by human structures each decade. To count lice, we searched 104 House Finch and 56 Hairy Woodpecker study skins (hosts) from the UCLA Dickey Bird and Mammal Collection. Specimens were collected between 1905 and 1932 across the states of Washington, Oregon, California, Idaho, Nevada, and Arizona. We documented two louse species parasitizing House Finches (host n = 104) and four parasitizing Hairy Woodpeckers (host n = 56), as well as abundant nits which were not identified to species. Of the 104 House Finches, 32 (31%) hosted Brueelia thorini and 26 (25%) hosted Philopterus sp., including 11 (11%) which hosted both species. Of the 56 Hairy Woodpeckers, just 1 (2%) hosted Menacanthus sp., and this individual hosted 6 Menacanthus sp. and 27 total lice. Additionally, 7 (13%) woodpeckers hosted Brueelia straminea s. lat., 4 (7%) hosted Picicola snodgrassi, and 11 hosted P. auritus s. lat.