In the dialect of the region where I live – the Oberbergische Land – potatoes are called “Ärdäppel” which means earth apple. In a shorter variant it is drawn together to “Ärpel”. And putting some potatoes in a bread dough (which makes it to a Ärpelbrot – Potato bread) was a good idea to all times. In former times this helps to save precious flour (especially in regions where grains do not grow so well like here in the Oberbergische Land), and nowadays we like the effect which potatoes have on the bread, keeping it moist and making the crumb soft and tender.
It is a great bread for all meals, and with the curved slashes it is a beautiful eye catcher as well.