I came across this variety in Oscar Will's 1941 seed catalog. I grew our plants from USDA accession PI 636232.
Here is the catalog page from 1941:
Mandan Earliana-1941.jpg
I was pleased with the deep red color, beautiful round shape and flavor of the fruits. Seeds are available from our store now:
https://twoseedsinapod.com/product/mandan-earliana/
EarlianaMandan.JPG