I have a several hundred-year-old farm. The wall in question is an interior wall and is at an angle to the exterior wall, meaning the room has two exterior walls and two interior walls, of which this is one. The wall already has two door openings and above these door openings is only a thin, about 1.5 cm, board that rests a couple of cm on a brick. The wall is partially brick but mostly some kind of clay lumps that you can pretty much tear apart with your fingers. The wall is one brick thick, so there is also no room for any type of reinforcement, etc. I can't see how the wall could reasonably be load-bearing. Am I right?
My experience is that the heart wall, i.e., the one running through the middle of the house lengthwise, is the most important. Everything else can be replaced with beams if necessary. I hope you get a better answer from someone who knows... but sometimes you don't get an answer at all, so my answer is better than nothing!
Examine the floor structure above the wall. If the beams run across the wall, there is a high risk that the wall is supporting the beams. If there is also a wall above, there is of course a high risk that the lower wall supports the upper wall.
I am grateful for all the info I receive, so your answer was welcome, Returia. And it also gave me an idea. There is a gigantic beam on the upper floor, and it rests on the piece of wall that runs along the middle of the house. So you're absolutely right, now that I think about it. For mulpac, there is a wall on the floor above, but it is only a couple of meters long due to the roof slope and two doorways. So it doesn't weigh that much. I'll keep thinking about it and am grateful for more opinions.