Warfare was not a part of everyday life for many Anglo-Saxons and Vikings. Despite all the heroic deeds in tales and sagas, a grown man would have seen a major conflict about once every twenty years. And even then he would had to have been in the wrong place at the wrong time to become involved. Being even wounded in a clash would be a very serious thing. Your chances of avoiding blood poisoning or overcoming infection were slight, often resulting in an agonising and lengthy death.
Whilst it is true that it was a thegns duty to serve his king in times of trouble, (this is also true to a greater extent for the Viking ruling classes), this would often be in a policing action rather than a bloody clash. No one in their right mind would contradict an armed thegn and his companions or Gesithas (pronounced as 'yeaseethass') with the authority of the King behind them.
It was not a time of men challenging each other in heroic duels (was there ever a time like this?), but a time for the thegns to organise repairs to bridges and roads. If he lived by a port, then his duties would require him to deal with the maintenance of ships and quays. Only on the rarest of occasions did these duties run into warfare.
The whole idea that the entire country took to arms with pitchforks and scythes is also a fallacy. To defend your home is one thing, but to die when you can run to save yourself was more realistic. The only people who had to abide by any duty of standing with their lord were the warriors as can be seen by the account of the Battle of Maldon. What chance did the farmers have against professional Warriors anyway?
The concept that the Vikings slaughtered peasants wholesale is far from the truth as well. Life then was based solely upon the land and how it could feed you, and without the local populous in good working order, their farms and livestock intact, you and your army would starve. You don't catch the Viking army doing a spot of vegetable gardening in the sagas to feed themselves.
From the tribal wars of the early Anglo-Saxon invaders to the Viking and Norman Conquests of England in the eleventh century, Britain had a long and bloody history, but it has to be seen in it's context. After all, an uneventful normal humdrum life didn't make for great headlines, even in the Anglo Saxon Chronicles.