Broken square
Broken square usually refers to an infantry square collapsing or breaking up in battle.
Specific incidents that this expression may refer to are both in the Mahdist War in the Sudan:
Frank Richards, a soldier in the Royal Welch Fusiliers circa 1901, stated in his memoir entitled 'Soldier Sahib': "If a Welshman went into a pub where a Highland soldier was, of the regiment whose square was once broken by the Mahdi's dervishes in the Sudan, he would sometimes ask for a "pint of broken-square." Then he would have his bellyful of scrapping for the rest of the night, because this was an insult the Highlanders could not forgive." This anecdote is frequently treated as fact.
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