History

Petteia (Greek: πεττεία, "pebbles") is attested from Homer onward and was certainly played before the fifth century BCE. Greek authors, including Plato and Aristotle, used it as a philosophical metaphor — the game was culturally ubiquitous enough that its moves and positions were common reference points in serious writing. Greek tradition held that it was of Egyptian origin, though no Egyptian antecedent has been identified with certainty.

By the second century BCE the Romans had adopted it as Ludus Latrunculorum — "the game of little soldiers" or "the bandit game." Roman writers from Varro to Ovid to the author of the Laus Pisonis describe it as a prestige game of pure skill. Boards have been found scratched into the steps of the Forum, the Colosseum, and military forts across the empire from Hadrian's Wall to Syria. Pieces survive in ivory, bone, and glass.

The game is last mentioned in Greek in the second century CE and in Latin at the end of the fourth. It may have survived in some Roman provinces, and a tenth-century Persian poem describing a game called Nard — not the backgammon variant but a separate strategy game — provides what may be the only clue about the function of the special dux piece found in some Roman sets.

The rules are reconstructed with significant uncertainty. The core custodian-capture mechanic is agreed upon by all scholars; the dux variant and starting arrangement are more debated.

Play — vs AI Opponent

Scholarly note: Rules follow Cyningstan's Botermans-based reconstruction. You play White (marble pieces); the AI plays Black (onyx pieces). Click a white piece to select it, then click a destination square. The AI uses minimax search with alpha-beta pruning. Enable the Dux variant to add one immortal commander piece per side.
⬜ Petteia / Ludus Latrunculorum Configure options and click New Game
White (You) —
Black (AI) —
Move —
MILES AD BELLUM PARATUS — the soldier stands ready for war…
Click piece to select · Click destination to move · Blue highlight = valid moves

Rules

The board
An 8×8 grid of squares. White fills rows 1–2; Black fills rows 7–8 (all 16 pieces per side). In the Dux variant, each player has 8 pieces in row 1/8 and their Dux in the centre of row 2/7.
Movement
On your turn, move one piece any number of squares in a straight horizontal or vertical line — like a rook in chess. A piece cannot land on or jump over any other piece.
Custodian capture
An enemy piece is captured by sandwiching it between two of your pieces along a horizontal or vertical line. The captured piece is immediately removed. A single move may create multiple custodian captures simultaneously — all captured pieces are removed. It is safe to voluntarily move into a sandwich: a piece stepping between two enemies is not captured.
The Dux (Ludus Latrunculorum variant)
Each player has one Dux — a commander piece marked differently. The Dux moves and captures like any other piece, but the Dux itself can never be captured. It can participate in sandwiching enemies but cannot be sandwiched. Based on the Persian Nard description (10th century CE).
Winning
Win by reducing your opponent to a single piece (unable to wage war further), or by completely trapping them so no move is possible. A draw may be agreed if no conclusion is apparent.

Why the Game Tends Toward Draws

Wally J. Kowalski observed that Petteia is prone to draws because the custodian-capture rule makes pieces very difficult to actually take — there is substantial jockeying for position before any capture is possible, and both sides can often build interlocking formations that block progress indefinitely. The voluntary sandwich rule (you can step between two enemies without harm) adds a further defensive tool.

It is likely that experienced Greek and Roman players developed strategic principles — offensive formation patterns, forced-march sequences, ways to break interlocked positions — that have not survived. The Laus Pisonis (praise poem for a Roman aristocrat, first century CE) describes a particularly skilled player who could "see a hundred moves ahead" and who played both colours simultaneously for a demonstration, suggesting the game admitted of considerable depth.

The commentator in the Cyningstan discussion thread raises the possibility that the objective was territorial (like Go) rather than eliminative — this is not impossible, and would resolve the drawish problem, but no ancient source supports it explicitly.

Sources: Cyningstan (Damian Walker), "Petteia" and "Ludus Latrunculorum," cyningstan.com (rules based on Botermans). Ancient sources: Plato, Republic 487c (petteia as metaphor); Varro, De Lingua Latina vi.64 (latrunculi); Laus Pisonis 190–208 (skilled Roman player); Ovid, Ars Amatoria ii.208 (women and the game). Archaeological evidence: boards at Hadrian's Wall forts, Corinium, and across the eastern Empire; glass, bone, and ivory pieces in Roman collections. Dux variant: derived from the Persian game Nard as described by Firdausi, Shahnameh, c. 1000 CE.