Alfred,
I trace my Paternal GGG Grandfather Samuel Remund to Muleberg Switzerland just Northwest of Bern, this we can trace back in Switerland to 1530. My Y-DNA haplogroup on Big Y FamilyTreeDNA was also R1b L21 subclade DF13. All others after this were private mutations, so yes appears somewhat rare. My Guess for our Family,they came into the British Isles over 4000 years ago then left around 500AD during the Germanic invasions. They seemed to have settled in Brittany France,then as French Huguenots immigrated to Switzerland in the late 1400’s, this our best guess considering history and distance Echo’s of Family history.