Recent re-examination of the evidence shows this was a misinterpretation – it was a tree-trunk coffin placed centrally in the first, timber, chapel at around the time Æthelflæd founded the burh, in 913 AD.The tree-trunk coffin may have been placed there as an object of commemoration or veneration of St Bertelin.It was first made of wood, and later rebuilt of stone.It has been rebuilt twice since, and the ruins of the 19th century gothic revival castle on the earthworks incorporate much of the original stonework.Stafford was one of Æthelflæd's military campaign bases and extensive archaeological investigations, and recent re-examination and interpretation of that evidence now shows her new burh was producing, in addition to the Stafford Ware pottery, food for her army (butchery, grain processing, baking), coinage and weaponry, but apparently no other crafts and there were few imports.
In 1206 King John granted a Royal Charter which created the borough of Stafford.
In the Middle Ages Stafford was a market town, mainly dealing in cloth and wool.
In spite of being the shire town, Stafford required successive surges of external investment from the time of Æthelflæd to that of Queen Elizabeth I.
She and her younger brother King Edward the Elder of Wessex, both children of King Alfred the Great and Ealhswith, wife of Æthelred, ealdorman of the Angles of Mercia, were attempting to complete their father King Alfred the Great's programme of unifying England into a single kingdom.
Æthelflæd was a formidable military leader and tactician, and she sought to protect and extend the northern and western frontiers of her overlordship of Mercia against the Danish Vikings, by fortifying burhs, including Tamworth and Stafford in 913, and Runcorn on the River Mersey in 915 among others, while King Edward the Elder concentrated on the east, wresting East Anglia and Essex from the Danes.