I was wondering if there are any good games which actually have (what I consider) some of the essential elements of guerrilla warfare:

1. Smaller and/or less equipped/prepared/supplied force
2. No frontlines but fluid patches of held territory
3. Hiding amongst the population
4. Emphasis on recon and hit and run attacks
5. Emphasis on a war of attrition, attacking supply convoys, small groups of soldiers etc. to persistently inflict greater losses upon enemy than self


The closest game I can think of is Jagged Alliance 2, but it only has a gradual decrease in enemy held territory, not their overall strength.
The x-com type game have elements but in those games the enemy get stronger as you carry on the fight, not weaker, and there is no real supply issues for the invading force.
Outcast had some elements of this, but obviously it was not the emphasis.
Games like Far cry 3/4, Red Faction: Guerrilla etc. have elements of this too but they just simulate taking a number of stronghold without actually simulating a Guerrilla war.

Does anyone know any games that fit the bill?

I haven't played it myself, but The Saboteur would seem to be what you're looking for.

Also maybe Freedom Fighters? That's not on GOG though.

We are the Dwarves may be.
It was at 80% off.

Freedom Fighters was fun too.

NVM

The first thing that popped into my mind was AI WAR: FLEET COMMAND.

Jagged Alliance 2 (especially with 1.13) ticks some of those boxes and definitely has a guerrilla warfare vibe to it. It ticks 1. and 2., but 3., 4. and 5. only partially.

There isn't an emphasis on recon and hit and run tactics, but you can employ them, especially the latter. On the higher difficulties it can become necessary to whittle down massive attack / counterattack forces if you want to take or hold onto a position. You can also train rebels to hold onto positions you've already taken.
And I don't think you can wage a war of attrition, that is other than reducing a force with hit and run tactics. Possibly you can by taking enemy towns to slow down enemy soldier generation, but I'm not sure.

Yep Jagged Alliance was the closest thing I've ever played to guerrilla warfare.

Some nice suggestions, I've never even heard of freedom fighters before, it seems to be highly praised by everyone where I'm reading.

AI war is not one I would have thought of, but reading the description, it might actually fit the bill. I'll have to check it out, even though I was after something more, human military than space battles.

Any more ideas. I don't know why, but I feel like there is some obscure game out there that just nails guerrilla warfare that one of you guys know about.

The closest thing I know of is Commandos, but I don't think it covers your criteria better than Jagged Alliance 2.

Republic : The Revolution, although not exactly a guerrilla warfare, more like political activism warfare, its flawed and difficult to find but interesting nonetheless.

You could also give operation flashpoint a try, there's a whole guerrilla expansion for it.

am i the only one?
http://www.donkey-kong.org/

Crusader: No Remorse/Regret, STALKER, Vietcong and the earlier mentioned expansion of Operation Flashpoint

I play most RTS guerrilla.

Some games make this easier than others.

Does not work :-(

There's Mosby's Confederacy by Tilted Mill (Caesar IV, Children of the Nile).

"As John Singleton Mosby, one of the Civil War's most interesting and dynamic leaders, you are charged not with leading vast armies into battle, but with commanding small bands of skirmishers, scouts and guerilla fighters on opportunistic missions to scout, ambush, steal supplies and harass a larger and better armed force of Union soldiers, in this game of turn based strategy and real time tactical combat for the PC. "

I haven't played this myself, but it seems really interesting, even if the reviews are somewhat mixed. Would definitely pick this up if it came to GOG.

https://www.gog.com/wishlist/games/mosbys_confederacy

Wow, nice find. Reading the feature points on steam, it almost looks identical to the points I mentioned in my OP.

The user reviews are a bit mixed though, with some saying it gets repetitive and others that it feels unpolished.

I'll have to grab this on the next steam sale.