The dialects spoken by the Germanic settlers developed into a language that would come to be called Anglo-Saxon, or now more commonly Old English.[4] It displaced the indigenous Brittonic Celtic (and the Latin of the former Roman rulers) in most of the areas of Britain that later formed the Kingdom of England, while Celtic languages remained in most of Scotland, Wales and Cornwall, although large numbers of compound Celtic-Germanic placenames survive, hinting at early language mixing.[5] Old English continued to exhibit local variation, the remnants of which continue to be found in dialects of Modern English.[4] The four main dialects were Mercian, Northumbrian, Kentish and West Saxon; the last of these formed the basis for the literary standard of the later Old English period, although the dominant forms of Middle and Modern English would develop mainly from Mercian.
Old English was first written using a runic script called the futhorc, but this was replaced by a version of the Latin alphabet introduced by Irish missionaries in the 9th century. Most literary output was in either the Early West Saxon of Alfred the Great's time, or the Late West Saxon (regarded as the "classical" form of Old English) of the Winchester school inspired by Bishop Æthelwold of Winchester and followed by such writers as the prolific Ælfric of Eynsham ("the Grammarian"). The most famous surviving work from the Old English period is the epic poem Beowulf, composed by an unknown poet.
The introduction of Christianity from around 600 encouraged the addition of over 400 Latin loan words into Old English, such as the predecessors of the modern priest, paper, and school, and a smaller number of Greek loan words.[6] The speech of eastern and northern parts of England was also subject to strong Old Norse influence due to Scandinavian rule and settlement beginning in the 9th century (see below).
Most native English speakers today find Old English unintelligible, even though approximately half of the most commonly used words in Modern English have Old English roots.[7] The grammar of Old English featured a much greater degree of inflection than modern English, combined with freer word order, and is quite similar in some respects to modern German grammar. The Old English period is considered to transition into the Middle English period some time after the Norman conquest of 1066, when the language came to be influenced significantly by the new ruling class's French dialect called Old Norman