Polish-Prussian Border Pillars in Warmia

[Peterski]

They demarcated the 18th century border between Poland (Warmia) and Prussia-Brandenburg:

http://images68.fotosik.pl/808/7ec36fc6c7f417f8.jpg

http://images68.fotosik.pl/808/61b2b048e2058fce.jpg

http://images67.fotosik.pl/809/4d0ba01cf549e91b.jpg

http://images70.fotosik.pl/807/d6649ceecfef9590.jpg

http://images70.fotosik.pl/807/411da691b90236f7.jpg

On one side of the border the population was Lutheran and on the other side Roman Catholic:

https://www.theapricity.com/forum/showthread.php?251988-Catholics-in-Inter-War-Germany-by-county

Warmia in red, surrounded by Ducal Prussia:

https://upload.wikimedia.org/wikipedia/commons/f/f8/Ksi%C4%99stwoWarmi%C5%84skieIRP.png

https://upload.wikimedia.org/wikipedia/commons/f/f8/Ksi%C4%99stwoWarmi%C5%84skieIRP.png

Triangular-shaped Catholic area in East Prussia:

https://i.imgur.com/WIW92J5.png