Caesar is a board wargame depicting the ancient Battle of Alesia in which Julius Caesar and his legions defeated the Gauls under Vercingetorix. Originally published as Alesia in 1971, it was redesigned and reissued by Avalon Hill in 1976. Jon Freeman called it "one of the few legends in wargaming" for its relatively simple rules that still result in a tense and suspenseful game.
The basic concept of the game is the double siege, with Roman lines facing both inwards around Alesia, and outwards against Gallic relieving forces. The exact lines of the fortifications are preprinted on the game board; the Roman player starts by placing all the Roman counters, which may go anywhere outside Alesia, although there are advantages to placing them along the fortification lines. The Gallic player then places some counters inside Alesia, along with the counter representing Vercingetorix, and keeps the remainder offboard.
There are up to 24 turns in the game, divided into two "Assault Periods" of 12 turns each, representing the two days of the battle. During each turn, the Gallic player moves on-board units, then the off-board units (showing the other player the locations but not the numbers of the units off-board), then resolves combat with adjacent Roman units. The Roman player then moves his units, and resolves the resulting combat.
The object of the game is for Vercingetorix to escape from Alesia and move off the game board, in which case the Gallic player wins. If a Roman unit ever moves next to him, he is considered to have been captured, and the Romans win.
Since the Romans have too few units to cover all of the double line of fortifications, and do not know exactly the numbers of the off-board units, there is considerable guesswork in trying to anticipate where the breakout might occur. At the same time, the Romans can move rapidly along the fortifications and concentrate their forces, so the Gauls must commit strongly when they decide to make their move.
The original game design was Robert L. Bradley's first effort, and quite unwieldy, with a game board over four feet across, 1,000 counters, and poorly defined victory conditions. The 1971 release, characterized as a "semi-professional version" with limited sales, was a redesign that shrank the board and reduced the number of counters. After Avalon Hill acquired the game, Donald Greenwood undertook additional development, reducing the size of the board still further, and simplifying the mechanics of off-board movement.