O.E.
bannan "to summon by proclamation," a sense surviving only in
banns of marriage (1198; spelling with double
-n- attested from 1549), which also is partly from O.Fr.
ban "public proclamation," from Frank.
*ban, cognate of the O.E. word. Main modern sense of "prohibit" is from O.N.
banna "curse, prohibit," and probably in part from O.Fr.
ban, which also meant "outlawry, banishment." O.E., Frank. and O.N. words all are from P.Gmc.
*bannan "proclaim, command, forbid" (cf. O.H.G.
bannan "to command or forbit under threat of punishment," Ger.
bannen "banish, expel, curse"), from PIE base
*bha- "to speak" (cf. O.Ir.
bann "law," from the same root; see
fame). Sense evolved from "speak" to "proclaim a threat" to "curse."
Banned in Boston dates from 1920s, in allusion to the excessive zeal and power of that city's Watch and Ward Society.