 Historical linguistics provides the main basis for the theory, analysing the development and changes of languages, and establishing relations between the various Indo-European languages, including the time frame of their development.It also provides information about shared words, and the corresponding area of the origin of Indo-European, and the specific vocabulary which is to be ascribed to specific regions.The linguistic analyses and data are supplemented with archaeological data and anthropological arguments, which together provide a coherent model that is widely accepted.