Drawing data from a standard High German letter collection originating in Lower Saxony, 1877-1915, and later found in Wisconsin, Litty recreates the social networks of the letter authors and recipients to show their known and available linguistic repertoires. By coupling historical sociolinguistic methods with social network analysis, Litty shows which features are available to the authors and/or recipients and which are expected according to locations where each author/recipient spent time or had close, enduring contacts. Litty identifies non-standard and vernacular features present in otherwise Standard German writings to show how features recognized as regional, or which are now stigmatized in European standard German varieties, appeared in the American Midwest. Among the features presented are features of orality, Northern German features, general Low German features, and specifically Eastphalian Low German features. This analysis is a preliminary step in describing the development of the feature pool found in today's Wisconsin Heritage German speakers where it is unrecognizable when compared with European German varieties and indicates a new stage of early input to the koinéization of modern Wisconsin Heritage German varieties.