Diocese of Winona, MN
The Diocese of Winona, MN was formed in 1889 and consists of Winona, Wabasha, Olmsted, Dodge, Steele, Waseca, Blue Earth, Watonwan, Cottonwood, Murray, Pipestone, Rock, Nobles, Jackon, Faribault, Martin, Freeborn, Mower, Fillmore, and Houston Counties in Minnesota. The map provided plots the locations of the two Polish Roman Catholic Churches in this diocese. Given addresses were usually of the rectory and not the church building itself. The map markers correspond to the church building if you zoom in close enough (they will put you at the front door).
Here's a couple links to parish history:
St. Casimir, Wells, MN
St. Casimir, Winona, MN