The simple rules but complex interactions make it appealing to adults, children, and families. Risk was invented in 1957 by Albert Lamorisse, a French filmmaker, and it became one of the most popular board games in history, inspiring other popular games such as Axis & Allies and Settlers of Catan. European versions are structured so that each player has a limited 'secret mission' objective that shortens the game. The game can be lengthy, requiring several hours to multiple days to finish. The goal of the game is to occupy every territory on the board and, in doing so, eliminate the other players. Players may form and dissolve alliances during the course of the game. Turns rotate among players who control armies of playing pieces with which they attempt to capture territories from other players, with results determined by dice rolls. The standard version is played on a board depicting a political map of the world, divided into 42 territories, which are grouped into six continents. Risk is a strategy board game of diplomacy, conflict and conquest for two to six players.