A danegeld was not just an english tax, it was also used in Francia, and it did not necessaraily have to be a 'tax' in the proper use of the word. Charles the Bald was the first Frankish king to pay a danegeld in 845. This consisted of him handing over 7,000 lb's of silver to the viking leader Ragnar. 

 Source: The year 845 in the Annals of St Bertin. I'll come back later and rewrite this article unless anyone else has further input?