Wilfried, thanks for pointing to Goethe's role. In a letter to Herder, 1771, he wrote that he had heard the song "from the throats of the oldest matrons" while riding on horseback through rural Alsace. No broadside ("Fliegendes Blat") for the lyrics, as sometimes claimed.

Even if we take Goethe's and Freiligrath's versions to be faithful renditions of living folklore, both are bound to be folk-processed. As I hinted before, Freiligrath's idea about the historical facts being reported is highly questionable. It is quite possible that married-with-children and affianced theories coexisted and were mixed.

As a fact we know that versions starting like "Ick sach mijn heere van valckensteyn" were very popular in Germany and the Netherlands in the 16th century. (Here an indirect quote from a chronicle of Stralsund, Pommerania.)