During WWI there were Russian prisoners of war – mainly of Chuvash nationality – working on the Kégl estates. Alexander Kégl learned their language and recorded a number of their folk tales.

These people also kept in contact with the Kégl brothers after being reassigned elsewhere. They often turned to them with their requests, trusting in their humanity that they had experienced for several years. Some of these letters have been preserved in the Kégl collection (Kégl/127).