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Wetland ecosystems are experiencing a global diminution of ecosystem services as the assemblage and performance of the ecosystem functions generating these services are negatively affected by the degradation and loss of wetland area. While regional and national assessments have been undertaken to inventory change in wetland area and condition in the United States, no such effort exists at the same extent or grain for individual wetland functions. Existing field-based wetland functional assessments become increasingly cost prohibitive as the geographic area of interest increases, and remote functional assessments designed to address these costs do so via a trade-off of data resolution and accuracy. This dissertation seeks to address these shortcomings through the development, testing, and application of a Hydrogeomorphic Remote Assessment of Wetland Function (HGM-RAWF) for freshwater wetlands of the Mid-Atlantic Region, USA. This remote-based functional assessment uses the hydrogeomorphic approach to wetland functional assessment, in tandem with a field sampled set of 222 reference wetlands, to balance the specificity and robustness of field-based hydrogeomorphic functional assessment methods with the use of widely available remote sensing and spatial data that can be deployed at broad scales (e.g., HUC8 to HUC12 watersheds and EPA Level III Ecoregions). Efficacy testing of HGM-RAWF determined that it produces results similar to, or slightly underestimated than, its field-based counterparts across its intended geographic scales and application of this remote assessment to wetland conservation practices revealed the potential for HGM-RAWF to detect temporal change in function at timepoints spaced as short as five years. Despite some limitations, requiring further field and spatial data to address, the design and efficacy of HGM-RAWF at the watershed and ecoregional scale provide a framework that is adaptable across the country and lays the groundwork for a functional assessment capable of tracking the status and trends of functional performance at the national scale.