Instead of fighting the invaders, some English kings preferred to pay the Vikings to leave them in peace. These payments were called 'Danegeld'.
The Vikings collected tribute in other countries too. In Ireland in the 9th century they imposed a tax and slit the noses of anyone unwilling or unable to pay, and that is the origin of the English phrase 'to pay through the nose' meaning to pay an excessive price.
The English king who paid the most Danegeld was Aethelred II. During his reign (978-1016) nearly 40 million pennies were produced in order to pay Danegeld.
Finally Aethelred decided to fight and he introduced a new tax to pay for a larger army. However Aethelred was completely defeated and the Viking's leader, Knut, became king of England, and later king of Denmark and Norway as well.