Borders during the 1800's - Was crossing borders easy or difficult?

How difficult/easy was it for people to cross the borders between the various regions during the mid-1800's? For example, would it have been common for someone living in Strasburg, Westpreußen (Brodnica today) to marry someone from Śweidziebnia or Rypin which were part of the Russian Empire? Could people move back and forth easily? Could they relocate from the German area to the Russian area or from Russian to German?

I remember that it was pretty easy to cross borders then!

:D
1800's is a long time, depend when and where and for whom!

My great grandmother and her bothers (Klimowski family) were said to have been born in Brodnica - family stories, no documents - from about 1860 to 1870. One of the brothers married a Cymanski in about 1880. She, it is said, was born in Śweidziebnia. They had a son who listed his place of birth as "Reppien" on a WWI draft registration card. I'm taking that to be Rypin. On all of their US Census forms they are listed as being born in Poland (Russ), Poland Rus, Russian Poland, etc. If they were from Brodnica, I would think it would be listed as German Poland or some variation on that.

I'm wondering if instead of Brodnica, it might really be the much smaller Brodniczka, which is only ~5 km from Śweidziebnia. Brodniczka also would have been in the Russian part of modern day Poland.

I read that in the 1880s the Prussian government deported all Poles that did not have German citizenship to "Congress Poland", in order to reduce the number of Poles in Westpreußen (Royal Prussia or Pomorze), Provinz Posen (Greater Poland) and Oberschlesien (Upper Silesia). This was pretty harsh because many Poles lived for decades in the above mentioned provinces, they just never cared about getting the German citizenship.

After this procedure crossing the border between the German and the Russian Empire wasn't so easy at all without further ado. As a German citizen you needed a Passport that was rather expensive and wasn't given to politically "unreliable" people, likes patriotic Poles. Relocating from "Russian Poland" to the German Empire was almost impossible for people with Polish ethnicity. Ethnic Germans from Russia in contrast could relocate whenever they wanted.

Of course the frontier was not fortified, so it might have been possible to cross the border by foot illegally and make a visit to the neighbouring village on the other side of the border line. Perhaps some of the German Border Patrol men even tolerated that, but it surely was better not to get caught.