Kurath's chief research interest was historical linguistics and his primary goal was to use the Linguistic Atlas to reconstruct the evolution of American English from the relatively "pure" forms of English brought to the United States by the early settlers to the regional dialects that existed in the contemporary United States.
Kurath was convinced that language held a living record of events like the growth of trade and transport systems, urbanization, and population movements.
By plotting regional differences in vocabulary and pronunciation on maps, Kurath and other researchers assembled what they hoped was a visual record of the social processes that had transformed American English over the past 200 years.
Kurath gave the researchers explicit instructions about the types of informants who were considered appropriate for the project.
Kurath placed a priority on towns that were early American settlements or could be directly linked to them through historical records.