Sourced from Digital Commonwealth of Massachusetts who have an amazing collection and mission. There isn’t a lot of information on the individual prints, what you see is what you get. By my reckoning they date from between the 1900’s to the 1950’s.
In my travels to find out more about the Russian ones, I discovered that Kio is the name of Russian family circus, Кио цирк translates to Kio Circus. There is a fascinating article about them titled “Secrets of the Kio circus dynasty: how they sawed their own wives and tamed the jinn”, a total digression from the art but well worth the read!