The Anthropocene is characterized by human influence on the environment, including aiding movement of non-native species to new regions. The impacts of invasive species on native communities are complex, especially for generalist predators like the brown widow spider (L. geometricus). Brown widows are native to southern Africa but have hitchhiked their way across the world, with help the help of humans, and are now established on every continent other than Antarctica. Following introduction, the role humans play in aiding invasion success remains poorly understood. In my thesis, I explore the role of urbanization in aiding the invasion of the rapidly-expanding invasive brown widow spider (Latrodectus geometricus) in North America, and assess potential ecological impacts of invasion on native widows (L. hesperus, L. mactans, L. variolus) on a continental scale. The first chapter of my thesis describes the geographic ranges of all four widow species under two models: a climatic model that uses climate variables alone to extrapolate the niche of each species in geographic space, and an anthropogenic model that includes human population density, as a proxy for urbanization, in addition to climate. I also quantified geographic overlap of L. geometricus with each native species to gauge the geographic extent of potential ecological impacts and identify species likely to be impacted. We found that native widow ranges were strongly limited by climate, whereas brown widows were more strongly limited by urbanization. Urban environments aid in invasion success by weakening the significance of climate on the realized niche of L. geometricus and facilitating establishment. Constraint to urban environments mitigates the magnitude of ecological impact by limiting the geographic extent of impact to cities. As L. geometricus expand their range, it is unclear how they share resources with their relatives and competition for climatic resources puts native species at risk of ecological impact. Thus, for the second chapter of my thesis, I use climatic niche overlap models to study how climatic niche partitioning sympatric geographic distributions of native widows compared to L. geometricus. We found that native species generally show weak niche overlap and have more strongly partitioned niches, with the exception of L. mactans and L. variolus which showed strong overlap and niche equivalency. We also found L. geometricus’ strongly overlap with native widows. This overlap may suggest that although brown widows are competing with native widows for climatic resources, differences in diet or urban microhabitats promote coexistence, or it is also likely that it is too soon to see the effect of competition preventing co-occurrence at large spatial scales. The results of both studies paint a picture of a biological invasion at a large spatial scale that provides valuable insights on the niche dynamics of brown widow invasion in the context of the native communities they invade.