A stone inscribed with Latin writing and Greek letters as well as Christian symbols – all dating from the 7th century – has been excavated at Tintagel Castle and will go on display at the Cornish stronghold from Saturday 16 June, English Heritage announced today (Friday 15 June).

Inscribed writing from the early Middle Ages rarely survives so this new discovery is particularly unusual. The 1300 year-old letters, words and symbols appear to be the work of someone practising writing a text. They indicate that this person was familiar with both the informal style of writing used for documents and the formal script used in the illuminated Gospel books of the period. This lends further weight to the theory that Tintagel was a royal site with a literate Christian culture, and a network of connections stretching from Atlantic Europe to the eastern Mediterranean.

The stone includes Roman and Celtic names – ‘Tito’ (Titus) and ‘Budic’ – hinting at a thriving multi-cultural community in this corner of Cornwall. The Latin words ‘fili’ (son) and ‘viri duo’ (two men) also appear. The stone itself – a two-foot long piece of Cornish slate – served as a window ledge in a building which seemed to be part of a major early medieval settlement.

The stone was discovered last summer as part of an ambitious 5-year project at Tintagel Castle, commissioned by English Heritage and undertaken by the Cornwall Archaeological Unit (CAU). Previous finds dating from the same period include fine tableware from as far away as Turkey, decorated Spanish glassware, and evidence that those at Tintagel Castle were feasting on pork, fish and oysters during “Cornwall’s First Golden Age”.

Speaking of the inscribed stone, English Heritage Curator Win Scutt said: "It's incredible to think that 1300 years ago, on this dramatic Cornish cliff-top, someone was practising their writing, using Latin phrases and Christian symbols. We can't know for sure who made these marks or why, but what we can say is that 7th century Tintagel had professional scribes who were familiar with the techniques of writing manuscripts - and that in itself is very exciting.

"Our ongoing research has already revealed the extent of Tintagel's buildings and the richness of the lifestyle enjoyed here. This latest find goes one step further to show that we have a literate, Christian community, with strong connections from Atlantic Europe to the Mediterranean. Writing was a privileged pursuit, undertaken by specialist scribes attached to the Church or wealthy households. The discovery of this stone supports the idea that Tintagel was an important, thriving trade port, and a high-status settlement which could have been the seat of Cornish kings."

Expert on writing Michelle Brown from the University of London has been charged with deciphering the inscription, along with textual expert Oliver Padel, and she explains that the style of writing is as intriguing as the words themselves: "The survival of writing from this period is rare and this is a very important find, especially in terms of the continuity of a literate Christian tradition in post-Roman Cornwall. The lettering style and language used, as well as Christian symbols exhibiting Mediterranean influence and contacts, all reveal precious clues to the culture of those who lived at Tintagel in the 7th century.

"The text features a mix of Latin script with some Greek letters, and a distinctive monogram. It suggests a high level of literacy and an awareness of contemporary writing styles associated with the early illuminated manuscripts of Britain and Ireland. Other examples of writing in Cornwall and Western Britain at this period take the form of monumental inscriptions on stones, but this example is quite different, with a writing style and layout suggestive of a competent scribe from a Christian background, who was familiar with writing documents and books and who was practising a series of words and phrases rather than carving a finished inscription."

CAU Principal Archaeologist Jacky Nowakowski directed the dig and said: "The writing revealed itself when the stone was cleaned. We knew straight away that this was something rather special. It's the kind of find archaeologists dream of discovering, and we were amazed to uncover it hidden within the remains of an ancient building."

The inscribed stone is the second example of early medieval writing to be found at Tintagel. The first, discovered in 1998, was a stone inscribed with several words including the Celtic name 'Artognou', which many wrongly took to be a variant of the name 'Arthur'.

Like the Artognou stone before it, the newly discovered stone will be the subject of much analysis. X-ray fluorescence (XRF) analysis has not revealed the survival of any colouring, but it is hoped that high resolution scanning will reveal how the marks were engraved. In the meantime the stone will go on display at Tintagel Castle from Saturday 16 June.