Here’s a set of free wargames rules for operational level actions during WWII. Battalions are represented on a 2×2 base, and the entire thing is inspired, it seems, by Volley and Bayonet.
Mega Blitz Rules
Mega Blitz is a set of free wargames rules for operational level games set in the 20th Century.
Kampfgruppe Ost WWII Rules
Kampfgrupp OST is a simple Hex based Operational level WWII game circa 1944-1945 East front.
Assault Gun World War II Operational Level Rules
Assault Gun is a set of free wargames rules by David Kershaw. David writes:
This rule set is designed to allow players to simulate large actions of the Second World War using miniature models. Each division is represented by less than 10 bases (regiments and battalions), so players can command several divisions each, and play a recognisable action of the Second World War.
The rules originally were available on Yahoo Groups, but with that site shutting down in 2018, I have archived the files here.
Not Quite Mechanized rules
Chris Kemp offers Not Quite Mechanized, a free set of operational level WWII rules. With the great emphasis on skirmish rules these days, it’s refreshing to see a set of large scale rules. Here’s what Chris has to say on why he decided to write an operational level set:
The idea for NQM began in the 1980’s when there was a dearth of fast games that allowed large multiplayer games to flow smoothly with a minimum of fuss. My experience of large cloth-model games at RMA Sandhurst with Dr Paddy Griffith and others, created a yearning to be able to re-create the vast sweep of those games, but with a far less intrusive umpire load. The players would be able to handle all the low-level combat themselves, leaving the umpire(s) free to concentrate on the high level decisions. Oh, and just to make it harder, the game had to be able to handle a couple of players wanting to have a knock-about on a Friday evening. Whether or not I succeeded, you can judge for yourself.