Old Welsh (Welsh: Hen Gymraeg) is the label attached to the Welsh language from about 800 AD until the early 12th century when it developed into Middle Welsh. The preceding period, from the time Welsh became distinct from Common Brittonic around 550, has been called "Primitive" or "Archaic Welsh".
Many poems and some prose have been preserved from this period, although some are in later manuscripts, for example the text of y Gododdin. The oldest surviving text entirely in Old Welsh is probably that on a gravestone now in Tywyn church, thought to date from the 7th century. A text in the Lichfield Gospels called the Surrexit Memorandum is thought to have been written in the early 8th century but may be a copy of a text from the 6th or 7th centuries.
surexit tutbulc filius liuit hagener tutri dierchi tir telih haioid ilau elcu filius gelhig haluidt iuguret amgucant pel amtanndi ho diued diprotant gener tutri o guir imguodant ir degion guragon tagc rodesit elcu guetig equs tres uache, tres uache nouidligi namin ir ni be cas igridu dimedichat guetig hit did braut grefiat guetig nis minn tutbulc hai cenetl in ois oisau
Tudfwlch son of Llywyd and son-in-law of Tudri arose to claim the land of Telych, which was in the hand of Elgu son of Gelli and the tribe of Idwared. They disputed long about it; in the end they disjudge Tudri's son-in-law by law. The goodmen said to each other 'Let us make peace'. Elgu gave afterwards a horse, three cows, three cows newly calved, in order that there might not be hatred between them from the ruling afterwards till the Day of Judgement. Tudfwlch and his kin will not want it for ever and ever.
The text shows many of the early spelling conventions of Welsh, when the basic Latin alphabet was used to represent the phonology of Old Welsh. At this stage, the use of ll to represent the lateral fricative /ɬ/ (liuit > Llywyd) and dd to represent /ð/ (did > dydd) had not been developed. The Latin letter u was used to represent the diverse sounds /ʉ/, /ʊ/ and /v/, which became u, w and f, v respectively, by the medieval period.