Glottology

Historical linguistics, also called diachronic linguistics, is the scientific study of language change over time. Principal concerns of historical linguistics include:

Modern historical linguistics dates from the late 18th century. It grew out of the earlier discipline of philology, the study of ancient texts and documents dating back to .

At first, historical linguistics was comparative linguistics. Scholars were concerned chiefly with establishing language families and reconstructing prehistoric proto-languages, using the comparative method and internal reconstruction. The focus was initially on the well-known Indo-European languages, many of which had long written histories; the scholars also studied the Uralic languages, another European language family for which less early written material exists. Since then, there has been significant comparative linguistic work expanding outside of European languages as well, such as on the Austronesian languages and various families of Native American languages, among many others. Comparative linguistics is now, however, only a part of a more broadly conceived discipline of historical linguistics. For the Indo-European languages, comparative study is now a highly specialised field. Most research is being carried out on the subsequent development of these languages, in particular, the development of the modern standard varieties.

Some scholars have undertaken studies attempting to establish super-families, linking, for example, Indo-European, Uralic, and other families into Nostratic. These attempts have not been accepted widely. The information necessary to establish relatedness becomes less available as the time depth is increased. The time-depth of linguistic methods is limited due to chance word resemblances and variations between language groups, but a limit of around 10,000 years is often assumed. The dating of the various proto-languages is also difficult; several methods are available for dating, but only approximate results can be obtained.

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