It was in 1906 when James Curle, a lawyer and antiquities enthusiast, discovered the arm guard, at the Trimontium fort, near Newstead, in the Scottish Borders. Trimontium was the largest fort erected by the Romans after they built Hadrian's Wall in the 1st Century.

Curle found a collection of scraps of metal and thought that he had found chest and shoulder armor. The fragments, which numbered more than 100, sat neglected for nearly a century, until museum officials started to piece them together. When they did, they discovered that it was indeed a gold arm guard, one of only three ever found from Roman imperial times. Museum officials think that the Romans just left the arm guard behind, during their withdrawal, in 410.

It was Julius Caesar's expeditions in 55 B.C. and 54 B.C. that first brought Roman troops to Britain in significant numbers, but it wasn't until the large invasion force of Claudius a century later that Roman conquest of Britain began in earnest. That conquest didn't extend into Scotland, but it did include most of what is just south of Scotland today.

The reconstructed arm guard will be on display in a new exhibition at the British Museum.