This book presents the use of kernelsmoothing, a family of methods adapted from fields such as signal processing, as a way to identify the true spatial distribution of linguistic forms at particular points in time. * Discusses the use of kernel smoothing in historical dialectology and new approaches to parameter setting * Presents a series of case studies from the history of Norwegian language * Investigates some of the major phonological and morphosyntactic shifts which transformed the language from Old Norwegian through Middle to early Modern Norwegian * Demonstrates how the kernel smoothing method allows us to see how these changes spread from place to place, and these findings are used to throw light on a number of more general research questions of interest to an audience beyond Scandinavianists * A step-by-step guide to kernel smoothing is offered, so that non-experts can apply the approach to their own data