Who were the traveling courtly singer/songwriters of germany in the twelfth and thirteenth centuries?

They were called the   Minnesinger.

Minnesingers were traditional singers and poets who lived between the 12th-14th Century Germany and performed the Minnesang (love songs).

The Minnesingers could belong to a high noble families but many were wandering artists who would go village to village to sing and earn a living.

Little accurate information is available in modern times though some of the later work from the 15th Century survives to this day.