Historians are appealing for people’s help in deciphering an inscription on a double-edged sword found in Lincolnshire in the 19th century.
The mysterious artefact was found in the River Witham in July 1825, and was presented to the Royal Archaeological Institute by the registrar to the Bishop of Lincoln.
The 13th century sword, believed to have been manufactured in Germany, features an inscription found along one of its edges and inlaid in gold wire.
It has been speculated that this is a religious invocation, since the language is unknown.
The inscription appears to read: +NDXOXCHWDRGHDXORVI+
The sword is on loan to the British Library from the British Museum as part of the Magna Carta: Law, Liberty, Legacy exhibition which runs until September 1.
Weighing 1.2 kg (2lb 10oz) and measuring 964 mm (38in) in length and 165 mm (6½in) across the hilt, it has been claimed that the sword could have easily sliced a man’s head in two if struck with sufficient force.