The projected Polish kingdom (Kreuznach conference and cession of Chełm to Ukraine)
<a href="//commons.wikimedia.org/wiki/User:Claude_Zygiel" title="User:Claude Zygiel">Claude Zygiel</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>, background from <a href="//commons.wikimedia.org/wiki/File:Vistula_river_map.png" title="File:Vistula river map.png">File:Vistula_river_map.png</a>