Blackadder - Upper Arm Sleeve Insignia/Patch identification?

[RTP]

Hi all,



First time posting - hopefully some one can help me out identifying this as I'm very much the novice!



In Blackadder goes Forth, which I imagine a lot of us have seen - in most episodes when Captain Blackadder and Private Baldrick are wearing their army issue uniform jackets - they bare a
"red I (capital i)"
insignia on their upper arm/shoulder sleeve. It's a sewn-on patch (see photos, below).



Because I'm new to this, I've been trying my best to research what this signifies online and in books, but without the correct lingo sometimes it's hard to define.

From my muddled stumblings - I believe it to perhaps be a Divisional/Battalion patch, or flash - signifying perhaps what Division/Battalion the boys are supposed to be in on the show.



However - it'd be great if someone with much better knowledge of this than I, could please tell me;

1) What the patch is supposed to signify - their division, brigade, something else entirely? etc



2) Is it a fictional patch, made up for the show, or does it actually represent a real-world something (e.g. an actual ww1 division)



3) Once clarified what it defines, it would be great to see other real-world alternatives to this patch (e.g. other variations, other divisional badges) that would be used on this location on the upper arm sleeve

Thanks for baring with me!









Rich