In 1868 officials launched an add campaign using that phrase ("Unus pro omnibus, omnes pro uno") to evoke a sense of duty due to widespread flooding in the alps and solicitations for donations as well as charity work. It is still the unofficial motto of Switzerland, and may have originated in a book / play of "The Three Musketeers" (1844).
Generally the intent of the saying is to stand as a united group against all attacks upon the group, the sacrifice of one for that group being a noble thing to the group.
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