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Within the Great Basin, exotic annual grasses, especially cheatgrass (Bromus tectorum), have increased fire frequency and altered fire regimes such that large areas of native shrublands have converted to annual grasslands. �This cheatgrass-fire cycle is well described, but less is known about the drivers of this fire regime change where it is most prevalent. Here, we examine the current fire regimes at the four most fire-prone Major Land Resource Areas (MLRAs) within the Great Basin: Humboldt Area, Malheur High Plateau, Owyhee High Plateau, and Snake River Plains. Preliminary results suggest that between 1980 and 2015, these 4 MLRAs, representing 41% of the Great Basin, have accounted for 53% of the 10,313 recorded fire polygons and 73% of the 13 million hectares burned. We combined data on seasonal weather, lightning strikes, wildfire start date, vegetation, and wildfire frequency to identify the primary drivers of wildfires in these focal areas. In addition, we created yearly predictive models, at the MLRA-level, to assist fire and fuels managers in identifying areas of elevated wildfire risk, information that might be useful for prioritizing fuel treatments or wildfire preparedness.