The oldest documents in German belong to the 8th c. of the Christian era. The history of the language before that time is a matter of reconstruction by inference, analogy, and comparative study. The ancestor of German, as of most European and many Asiatic tongues, is termed Indo-European, of which no trace remains. It was spoken for thousands of years, and was still current c.2500 bc. Authorities are divided as to whether the peoples who originally spoke it lived near the Baltic or the Caspian Sea. From Indo-European developed Primitive Germanic, a language which is also virtually undocumented. The most decisive change which differentiated it from Indo-European is the First Sound Shift (see Sound Shifts), a process which was completed by 500 bc. German is the successor to Primitive Germanic, from which it is distinguished, among other aspects, especially by the Second Sound Shift, which fixed the consonants of High German. High German early established its predominance, and persists as the normal spoken and literary language. (For Low German, which did not undergo this sound shift, see below.)
Documented High German is conventionally divided into the following four phases, the dates of which represent only a rough approximation: (1) Old High German (Althochdeutsch), c.770-1050; (2) Middle High German (Mittelhoch-deutsch), c.1050-1350; (3) Early New High German (Frühmittelhochdeutsch), 1350-1650; and (4) New High German (Neuhochdeutsch). The initials OHG and MHG are frequently used in English for (1) and (2) respectively, and ENHG sometimes for (3). OHG and MHG are not unified languages, but groups of spoken dialects. The documentation of OHG was entirely in the hands of clerics at monastic centres of learning; for the laity, regardless of rank, was illiterate in the early Middle Ages. Even in MHG the work of monks predominates, since the ability to read and write, though no longer exclusive to ecclesiastics, was not a common accomplishment even at courts. The clerics, whether they were monks or administrators holding office at courts, usually preferred Latin to OHG, and this, as well as subsequent neglect, largely accounts for the scarcity of documents in this oldest form of recorded German.
Both OHG and MHG are too dissimilar from modern German to be accessible without special study. OHG is the richer in sound, preserving a variety of vowels in its inflections. Towards the end of the OHG period Notker Labeo, a monk of St Gall, developed a new fluency of expression in his translations of Latin authors. In MHG the inflectional sounds of OHG were reduced to a mute ‘e’, but the vowel sounds of the stems are closer to the old language than to modern German. The notation of modified vowels (Umlaut), which was irregular in OHG, is systematically observed in MHG, which also developed a flexible and easily manipulated syntax. MHG produced for the first time a virtually standardized literary language, which is the vehicle of Minnesang and the courtly and heroic epics. In common use MHG remained almost as dialectally variable as OHG.
Early New High German, which developed from the late 14th c. onwards, exhibits a more obvious kinship with the modern language. Its vowels approximate to later use, and simplification of inflections goes a stage further. A special feature of the ENHG period is the development of a form of official language to be used for purposes of administration (Kanzleistil or Kanzleisprache, i.e. Chancery style). The Kanzleisprachen of Prague, Meißen, Mainz, and Vienna are especially notable. At the end of the 15th c. new printing techniques became a powerful factor in the standardization of German. In the 16th c. the wide dissemination of the Lutheran Bible influenced, by its strong and direct prose, the language even of Catholic regions. In 1578 appeared the first German grammar, the Grammatica Germaniae linguae by J. Clajus. In the 17th c. M. Opitz defended the merits of German and laid down rules for its literary employment; language societies, such as Die Fruchtbringende Gesellschaft, sought to purify it. From 1687 onwards German very gradually made headway in the universities as the language of lecturing and of scholarship. A setback to German occurred, especially among the German aristocracy, through the political prestige of the French monarchy under Louis XIV, which encouraged the written and spoken use of French and French forms of literature.
New High German came completely into its own in the 18th c., largely through the achievement of talented men of letters of the rising middle class. Important landmarks in the development of this language are Deutsche Sprachkunst (1748) by J. C. Gottsched, the lexicographical work of J. C. Adelung between 1770 and 1790, and the Deutsches Wörterbuch of J. and W. Grimm, begun in 1852 and completed (by other hands) in 1960. German orthography was standardized in 1880, and pronunciation was established in the form of ‘Bühnendeutsch’ by J. C. Siebs (1862-1941) in his Deutsche Bühnenaussprache (1898). Local dialects continue to be spoken and tinge the speech even of the educated, so that they indicate place of origin rather than social standing. For the correct spelling of modern German (Rechtschreibung) see Duden.
Low German (Niederdeutsch) is distinguished from High German primarily by the fact that it has not undergone the Second Sound Shift, so that High German Wasser is Low German Water, HG Teufel is LG Deubel, etc. The area covered by Low German was the North German plain and the Netherlands. Its best-known ancient literary monument is Der Heliand, and it achieved its greatest florescence at the time of the Hanseatic League (see Hanse) when it developed a standardized form for commercial use. Though in the west it prospers in the Dutch and Flemish languages (and, to a point, in English), in Germany it is a collection of dialects, known as Plattdeutsch, and is still spoken in country districts in the north. It differs from region to region; the best-known variations are Hamburger Platt, Holsteinisches Platt, and Mecklenburgisches Platt. All are in decline under the spread of High German as the language of the educated. Plattdeutsch has a literature, of which the best-known representatives are F. Reuter (Mecklenburg) and K. Groth (Holstein) in the 19th c., and R. Kinau (Hamburg) in the 20th c.


