u need to be in a City witch can be owned by differend nations, like Genton or Wham. Its not posible in Midham, Sutusk and Pitlow.
If for examble M nation own one of this citys - a M nation player IN this city can start a regional war with an city from an other nation.
every Fall 10 min after Legion War the Reginal war starts. All players in the area or city can take part in this war. they get RP if they win or lose.
If M nation city start a war against a V nation city and M nation win - they have a chance to own the other city too. The "Nation owned" gets higehr for M nation and lower for V nation.
one area can have max 2 RW's every Fall