The definition of the common burdens was part of the growth in power and sophistication of royal government; as kings’ demands on their people grew, so they began to grant immunities from secular burdens to churches and favoured individuals, reserving the military obligations necessary for all. To the ancient armyservice were added fortress- and bridge-work, the insistence on which gained increasing urgency under the pressure of Viking attacks. Indeed, as Nicholas Brooks concludes, ‘the development of royal authority in England was directly connected with the successful enforcement of public works and general military obligations so that an adequate defence against the Vikings was provided’.

This ‘development of royal authority’ can be seen through bridge-work in successive generations of the West Saxon dynasty. Alfred appears to have been the first king to insist successfully upon the performance of common burdens, to unite the people to resist the Vikings. Edward and his sister Æthelflæd used the common burdens in their wars of reconquest, imposing the common burdens as they built burhs. Æthelstan and his half-brother Edmund then turned the policy inwards, making bridge-work part of the new public peace. Under Edgar, this peace reached its apogee in an accepted and uniform order. And under Æthelred, all became disorder again.

Before it is possible to analyze this process, however, it is necessary to step back for a moment and re-consider the essential question, what was the purpose of bridge-work?

The Purpose of Bridge-work

Authors of general works on Anglo-Saxon governance necessarily mention the three common burdens, from which theoretically no-one was exempt, and thus refer to bridge-work in passing. Most, however, never pause to ask why an early medieval king would require all his subjects, who could be exempted from almost everything else, to build bridges. Bridge-work is seemingly too obvious to discuss. Only a scholar of an earlier generation, W. H. Stevenson, came close to stating this outright: the other two obligations, army service and borough-work, he argued, constitute ‘such primitive requirements of any organized state’ that it is not surprising or significant that they are not mentioned in the earliest charters, so they do not need explanation. In this context, however, even Stevenson omitted bridge-work, as if hesitant to commit himself on it.