You are a DESERTER. Once, you served in an army, mercenary company, or other such group of fighter-types, but no longer. You took what you could and fled. Anyone with potential ties to your group or who you interacted with while spending time with your organisation is likely to recognise you, and have a 3-in-6 chance of knowing of your desertion.
Draws inspiration from deus ex parabola's Zouave, Arnold K.'s original GLOG martial classes, and probably some other places I'm forgetting.
Start with (all stolen): medium armour, a shield bearing your former affiliation, a medium weapon, a weight on your conscience, good boots, an extra 10 coins
You get an additional +1 HP at A and C.
A: Fleet of Foot, Basic Training
B: Well-Travelled
C: Unperturbed
D: Danger Sense
Fleet of Foot: You move at twice speed while running away from a fight, and your entire party is never impeded by bad terrain.
Basic Training: You can tell a creature's HD after seeing it fight for a round, and have advantage on rolls during combat to do things other than attack.
Well-Travelled: You've been everywhere since you ran away. You can read road signs in any language, and have a 2-in-6 chance of knowing a single fact about any object from a Far-Off Land.
Unperturbed: You've seen a lot, both before and after you defected. You have advantage on saves against fear, and so do your allies if you roll and succeed first.
Danger Sense: You have a good nose for when things are about to go south. You can't be surprised, and can make a free attack at the start of combat at someone or something CLOSE, regardless of initiative.
Example Backgrounds (1d6):
Feel more than free to adapt these to your own games, settings, and characters as you wish, and of course to make your own or ignore them entirely.
(1) Riverspoke Piker: Peasant militia that guard the south-west border of the Commonwealth from attack. You can speak to and understand fish, voles, and beavers. They won't always speak back. Start with a chain shirt for armour, a pike as weapon, and a shield bearing a pair of beavers atop a wall.
(2) Sons of the Sea: A notorious pirate crew, feared across the True Sea. You weren't quite cut out for that life. You always know where to find the best place to drink in town, and in a pinch can drink sea water as though it were clean. Start with a scale-mail coat, a cutlass, and a shield displaying a white crown on a blood-red skull.
(3) 403rd Light Infantry Regiment of Their Liege: Foot soldiers in indentured service to the office of the High Liege. You can never be picked out of a crowd if you don't want to be. Start with hide armour, your choice of crossbow and 20 bolts or a club, and an unadorned shield.
(4) Fargrath Freelancers: A mercenary group, providing soldiers for hire to nobility across the land. One of the less notable houses in your time with them, but now on the rise. You can nick things as a 1st level Scavver. Start with a spear or sling, a worn breastplate, and a shield featuring crossed spears and an open eye.
(5) Celestial Legion Gamma-Blue-23: You fled so far and so fast, you left your home world and ended up in this one. Other otherwordly beings recognise you as being part of the Celestial Legion, and mundane folk have a 3-in-6 chance of knowing you're out of place (rather than recognising who you are). You may be actively hunted. Start with a weapon no one recognises, armour crafted from a never-seen-before metal, and a "shield" coloured in solid octarine.
(6) Siblings of St. Uryuvkos the Devout: A holy order of pious warriors, looking to spread their Holy Teachings and bring light to all the world; the strict code didn't sit quite right with you. You can see in the dark as though it were dim light, but can't read. Start with a club, a second-hand half plate, and a shield showing a purple rose in front of a set of scales.