Analysis of information sources in references of the Wikipedia article "Lute" in English language version.
Bletschacher (1978) has argued that this was due largely to the royal visits of Friedrich II with his magnificent Moorish Sicilian retinue to the towns in this valley between 1218 and 1237.
By 1500 the first written records confirm the existence of several families making lutes as a trade in and around Füssen in the Lech valley. Most of the famous names of 16th and 17th century lutemaking seem to have come originally from around this small area of Southern Germany. By 1562 the Füssen makers were sufficiently well established to set up as a guild with elaborate regulations which have survived (see Bletschacher, 1978, and Layer, 1978).