Why does each side have only five soldiers?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws and is regression-tested against the official 110-diagram repetition casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it against the engine before publishing.
Direct answer
Five, on the 1st, 3rd, 5th, 7th and 9th files, each with an empty point between it and the next. The arrangement is not a smaller version of a chess pawn line — the gaps are the point, because they leave the cannons long open lines from move one and let horses develop without a pawn break.
What the gaps do
They are why 炮二平五 is playable immediately: the cannon slides to the central file and its line to the enemy general contains exactly the two central soldiers. They are also why the opening is sharp from the first move, with no slow pawn-structure phase of the kind chess has.
No pawn structure
Because soldiers are spread out and never capture diagonally, they cannot form chains, cannot be doubled in any meaningful sense, and cannot create the locked structures that define chess strategy. Xiangqi strategy is about piece activity and the palace, not about pawn skeletons.
Related questions
Which files do the soldiers start on?
The 1st, 3rd, 5th, 7th and 9th, on the rank just behind the river.
Can soldiers defend each other?
Not diagonally, since they do not capture diagonally. Two crossed soldiers side by side can defend each other along the rank.
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