The Upper Susquehanna Valley region is thought to be the homeland of the Susquehannock Indians, historically known to reside in south-central Pennsylvania. The Susquehannock sites in this region, called 'Proto-Susquehannock' by many, are understudied and provide nebulous answers to the question of Susquehannock origins. This thesis provides a compilation of Proto-Susquehannock research including information on excavation history, site location, artifact assemblages, and past research on forty-five sites labeled as Proto-Susquehannock. Intended as background research for future Proto-Susquehannock studies, the thesis also delves into definitional problems hindering research in this area, focusing on terms such as protohistoric and Proto-Susquehannock and the pottery variants often associated with the Susquehannocks (Richmond Mills Incised, Proto-Susquehannock, and Schultz Incised) and the lack of consistent and operational definitions associated with each term. The thesis concludes with the statement that additional research is necessary in the Upper Susquehanna River Valley to successfully create a comprehensive history of the Susquehannocks.