mid-14c., proteccioun, "shelter, defense, that which shields from harm or injury; keeping, guardianship, act or state of protecting;" late 14c. as "that which protects," from Old French proteccion "protection, shield" (12c.) and directly from Late Latin protectionem (nominative protectio) "a covering over," noun of action from past-participle stem of protegere "protect, cover in front," from pro "before" (see pro-) + tegere "to cover" (from PIE root *(s)teg- "to cover"). A common Old English word for "protect" was beorgan.
The political economy sense of "system of fostering a country's industries by means of imposts on products of foreign competitors" is from 1789. As "a writing that guarantees the bearer safety or safe conduct" from mid-15c.; the modern underworld sense of "freedom from molestation in exchange for money" is attested from 1860. The ecological sense of "attempted preservation by laws" is from 1880 (originally of wild birds in Britain).
Also in medieval England, "the protection or maintenance of a lord or patron; sponsorship." To put (someone) out of protection meant to deprive him or her of the security of the protection of the kingdom's laws.