keyboard mapping

I was wondering. I don't got the keyboard yet so I don't know what kind there will be yet. But I think it might be a ps2 or the older bigger "din". I have got some ps2 to work when solder it to a USB, but not all. Now for my question:

Is it possible to solder on the cable to arduino (the smallest one) and keymapping them so they get regonized right somehow when connected to USB. I have seen some programs for IBM keyboards but I don't know what I will get and I use Swedish keyboard with åäö so I guessed they will not work correctly with the script.

Is there a tutorial on "how to solder the keyboard cable to the arduino" and "program for remapping" that is easy to use. I have not programmed for 16 years so I'm not familiar but I'm trying to read and learn.

Edit: I don't really understand, does the programming on the arduino save itself. So if I plug it out will it work on another pc or Mac? Or do I need to install the arduino program on another pc for it to work?

I do want to connect the keyboard to the arduino and then to USB on a PC or similar and get it to regonized all the keys so they are mapped right.

Here is an example for how to connect a PS2 keyboard to Arduino.

But I don't understand why you want to remap the keys, as the conversion between keys and their corresponding characters is done by the OS's keyboard-driver.

The keyboard is basically just sending scancodes when keys are pressed. A key at a spesific location is sending the same scancode regardless of its cap. So a swedish 'ö', a norwegian 'ø' and a french 'm' will send the same code because they are at the same location.

After uploading a sktech to Arduino, it will continue to run independent of a PC-connection.