Diplomacy (board game)
Diplomacy is a board game. In its standard form, it involves 7 players, each controlling one of the major European powers just before World War I: England, Germany, Italy, France, Russia, Turkey, or Austria.
Gameplay
Each player begins with 3 or 4 units, each being either an army or a fleet. Players then attempt to take over as many "supply centers" as they can. They can take over neutral supply centers, such as in the Balkans or Scandinavia, or they may take over other player's supply centers. If a player takes over a supply center, they get to build a new unit in one of their home territories.
Every player submits their orders at the same time, and all units move simultaneously. If two units attempt to move into the same space, they "bounce" and return to their previous position. However, if an adjacent unit is commanded to "support" one of the units, then that unit gains precendence, and moves into the disputed space.
The key of the game is getting other players to support your units' actions, and supporting theirs. For example, Russia and Turkey may chose to ally and attack Austria, supporting each others moves. However, there are no binding treaties of any kind, so players are always open to being "backstabbed".
A player wins the game by taking more than half of the supply centers on the map.
Alternate maps
There are many alternate maps and settings for the game of diplomacy. The most popular is the so-called "Youngstown" map, which keeps the European powers in similar positions, but adds the continent of Asia.