Just started this game. The text size is far too large regardless of which resolution setting I use. I can't find a file that allows me to change font size. Any help out there?

It sounds like you have the exact same problem I have on my laptop. My laptop has a 4k monitor and the game just can't support it. I did everything I possibly could, but could just not get it right. I ended up putting it on my desktop, which has a pretty old and low resolution monitor and it works fine.

Try lowering the resolution setting in game and/or of your PC itself.

If I ever find a fix I'll update this thread. Please do the same?

There is a file in C:\GOG Games\King Arthur II\Cfg\Constarray
Open the Constarray file at the very bottom you will find....
GENERAL_FONT_SIZE_MODIFIER=0
TOOLTIP_FONT_SIZE_MODIFIER=0

Change the modifier value, 0 is small 5 is max, may help may not, but this will help others struggling with tiny text.
Worth a look.

I found a solution to this problem, it is a scaling issue. Go to windows settings / system / display, under scale and layout, you need to change size of text, apps, and other items to %100. Any thing higer than this causes the text in the game to not display correctly.