Alfred the Great

Alfred's story is well known and justly famous.

Defeat and revival
In the campiagn of 870-1, Wessex fought the Danes to a standstill, and survived to fight again. But Guthrum caught Alfred napping in 878, and in Athelney marsh Alfred came close to final defeat - and now we could all be speaking Danish. But at Ethandun Alfred changed history.
http://historyofengland.typepad.com/blog/2011/02/7-alfred-the-great-and-the-fight-for-survival.html

Reconstruction
Alfred made good use of hte years between 878 and 892 - capturing London, re-ordering trade, reviving learning, re-organising the army and instituting the Burghal system.
http://historyofengland.typepad.com/blog/2011/02/8-reconstruction-and-defence.html

A Kingdom Defended
The danish wars of 892 - 896 were very different to those of 878. The Danes could not penetrate the Wessex defence, and eventually give up, and go home.
http://historyofengland.typepad.com/blog/2011/02/9-unshakeable-pillar-of-thewestern-people.html