Fire regime alteration is a known threat to the conservation of biological diversity. Specifically, altered fire regimes often result in changes in plant and animal species composition and ecosystem structure. The LANDFIRE Rapid Assessment (LFRA) project recently produced a series of maps including Fire Regime Condition Class (a measure of the departure of current vegetation from vegetation reference conditions), Fire Regime Groups and Potential Natural Vegetation Groups for the conterminous U.S. that can assist in assessing the threat to natural fire regimes and can help in establishing conservation priorities. We present the findings of an assessment of the ecological role and integrity of fire regimes across the conterminous U.S. based on LFRA data. In addition, we present examples of potential applications of the LFRA reference condition models and spatial data which could be applied outside of the U.S. Our analyses of the data reinforce that frequent fire return intervals dominate reference fire regimes across the assessment area and that approximately 80% of ecosystems and major habitat types are moderately-to-highly departed from their ecological reference conditions. Additionally, the results indicate that fire regime conditions do not differ substantially inside conservation areas or federally-administered lands compared to outside these areas.