why is it believed that gun salutes are set off in odd numbers

Gun salutes are traditionally fired in odd numbers because, in European naval custom, even numbers were associated with death or mourning, while odd numbers were seen as more auspicious or honorary. Over time this superstition hardened into protocol, so formal salutes for living dignitaries and state occasions stayed odd-numbered, and that pattern continues in modern militaries.

Old beliefs about numbers

Early modern sailors and officials believed odd numbers brought luck, while even numbers could signal misfortune. In some traditions an even number of shots explicitly indicated that a ship’s captain or another key officer had died during the voyage.

Because of this, using even numbers in a ceremonial welcome would send the wrong message, almost like announcing a death instead of paying honor. Odd numbers, by contrast, marked a positive salute of respect to the person or event being recognized.

From superstition to formal protocol

By the late 17th century, British naval administrators such as Samuel Pepys were associated with efforts to regularize gun salutes by fixed numbers. In that process, the older superstition about even numbers and death helped lock in the rule that official salutes should use odd numbers only.

Modern regulations still reflect this heritage, specifying odd-numbered salutes (5, 7, 11, 15, 19, 21, etc.) according to the rank of the person being honored. The famous 21-gun salute is simply the highest of these odd-numbered honors, not an exception to the rule.

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