The military uniform was from the Austro-Hungarian Empire which was in power when our ancestors left for the US. All men of age had to serve in the military. The man seems to be too young to be Jan Černík, who would have been in his mid-60s by the time this photo was taken. Perhaps it was one of his daughters and her husband and kids.

Taken by Ephraim Clements when he shared a space with Anderson Photographers (father and son) in Wahoo.