The Major in The Purple Children by Ellis Peters is an experienced soldier; he feels comfortable in his role as a warrior. It is clear that he immediately understands why the sentry was taken in by the seemingly innocent girl of fifteen.
The major had been in the country for over a year, and was accustomed to the local style of warfare, to the ugly demands it made upon him, and the satisfaction he sometimes felt in their ugliness, which frightened and depressed him more than anything else.
Despite his hardened outlook on warfare, he is patient with the young sentry. Although the sentry is embarrassed at his lapse of judgment, he tries to argue that putting up a flag isn't much of a crime. The major smiles at the young sentry's naivete. As an experienced soldier, he knows that a flag can symbolize many things: patriotism, honor, and even rebellion. To him, the children have put up the Greek flag as a symbol of their dissent against the British occupiers, and the Major knows that he must find the girl who made it possible. He knows that the flag is a powerful enemy that cannot be 'imprisoned, or exiled, or killed.' He also understands that the natives will draw fresh courage from every Greek flag that goes up.
Having spent a year searching the houses for 'explosives and arms, for subversive literature in the native tongue, for wanted men on the run,' the major is exasperated and disgusted that the war has now descended to fighting little children putting up rebel flags around the town. The major just wants to get the whole situation over with; he needs to find the girl. He reasons that once he has the girl, the boy will also reveal himself. He tells the headmaster that he would rather deal with the grown-ups than the children, but the headmaster tells him that the children also have their duty and must be true to their ideals. Although the major is a little irritated with the nonchalance of the headmaster, he does not field a clever retort; indeed, he is in rather an ironic situation. The major chooses to overlook the headmaster's sly comment about 'looking for someone more than usually embarrassing as an opponent.'
When he marches in to inspect the senior forms, the Major's confidence and triumph is arrested when he realizes that all the children have purple dye on their faces. He is shamed by the courage and resilience of the children.
He had come looking for a marked outcast. He beheld a regiment, a Pyrrhic phalanx of embattled children, all their delicate olive faces spattered from forehead to chin with the resplendent purple of royalty and mourning.