The Long Creek Site was excavated in 1957 as part of an impact assessment of the Boundary Dam construction and subsequent reservoir. The site was the deepest stratified site that had been uncovered on the Northern Plains at the time of excavation. The cultural chronology at the site helped define the chronology for the entire northwestern Plains region. Archaeological investigations over the past 45 years have uncovered a wealth of knowledge, which when applied to the Long Creek assemblage, change our interpretation of it.