One of the oddities of the plague in Britain and Ireland is the absence of any visible impact on political history. The few kings who died of plague were apparently replaced peacefully from within their kingdom, if not their dynasty. The effects of the plague on the church, particularly in the loss of bishops, may suggest that the effects of the plague on political history have not been appreciated enough, though the infrastructure of the early medieval kingdoms was significantly stronger than the fledgling church in Britain. While churchmen were mourned in Ireland, it doesn’t seem to have caused a crisis.
The Northumbrian plague of c.684-688 gives us an opportunity to look at the effect of a specific wave on plague on politics and particularly warfare. We don’t know exactly when this round of plague began in Northumbria. We know that it began at least a year before Cuthbert became bishop, so at least 683-684. So this means that the plague was present in the kingdom, indeed at Lindisfarne, when King Ecgfrith sent ealdorman Berht with an “army” to Ireland to wreck devastation and perhaps more importantly take many hostages. We know that they attacked several churches and monasteries and took clerical hostages. We can probably assume that they took secular hostages as well. These hostages, perhaps including secular exiles, living in the monasteries were probably Ecgfrith’s real goal. Regardless of King Ecgfrith’s motivation, the plague did not stop him from sending an army far from home. Indeed, this is the only known English war band to be sent on a campaign by sea to Ireland or anywhere else in the early Anglo-Saxon period.
This attack on Ireland was roundly condemned by churchmen including within Northumbria. King Ecgfrith had apparently been in contact with the wandering English bishop Egbert who urged him not to attack Ireland. Egbert was either living in Ireland or Pictland at the time, so King Ecgfrith’s Irish campaign was discussed long distance for some time before it was undertaken. Given that the Northumbrians were not known for having a navy it would have taken some time to build the ships necessary to take the warband there. This raid was no impulse by a rash king. Perhaps the planning that went into the raid made it more likely that it would proceed even during the plague.
The Pictish rebellion just a year after the successful raid on Ireland doesn’t seem very wise. King Ecgfrith had brutally put down the previous Pictish rebellion about a decade earlier. After such a display of power in Ireland, why would King Bridei ap Beli have thought now was a good time to rebel? Although Berht brought back over 20 hostages, they still may have lost many of their warriors in Ireland, potentially weakening their army. They could have lost more warriors to the sea or battle injuries. Perhaps after such a victory Ecgfrith’s tribute demands went up so high that Bridei couldn’t or wouldn’t pay. The plague, of course, is another factor. If the plague wasn’t in the north, as Adomnan implies, then perhaps Bridei thought that Northumbria had been weakened enough by the plague that he could not field a typical Northumbrian army. I don’t think the plague has been considered before as a factor in the Pictish rebellion or in Ecgfrith’s unexpected defeat before.
King Bridei did have a plan. He had been waging war on his other borders for several years, racking up victory after victory. Presumably his warband was at its peak in size and experience. Even so he planned an ambush for Ecgfrith’s war band that was a critical part of his success. It is believed that the campaign is memorialized on the stone to the right with ravens picking on Ecgfrith in the lower right corner.
We will never really know what effect the plague had on events in 684-685. It didn’t stop King Ecgfrith from launching two major campaigns. If the plague did weaken Ecgfrith’s forces or give Bridei the belief that this time he could win, then it played a significant role in the unexpected death of Ecgfrith. In turn, the death of Ecgfrith in battle was one of the most significant events in the history of the Northumbrian kingdom. It was from that point that Bede marked the deminishing of Northumbrian power.
In an era when warfare is so frequent and local, it is difficult to to discern the role the plague may have played. It is likely that plague weakened regions were more vulnerable to attack, if the attacker would venture into a plague stricken area. Of course, it takes more than a few years for the population to recover a plague. The plague would also lower a regions ability to produce crops as workers are lost and crops go unharvested. It may have played a role in the smaller independent regions ultimately being incorporated into the larger kingdoms. They would be unable to resist incorporation and would have wanted the protection. It may not be a coincidence that many of the smaller independent regions listed in the tribal hinge disappear shortly after the plague of 664.
Bede, Life of Cuthbert
Bede, Ecclesiastical History of the English People