"Scapegoat" may rest on a mistranslation. The English word exists because a translator read one obscure Hebrew word as a description, when it may have been a name.
The source is Leviticus 16, which describes a ritual for the Day of Atonement. Two goats were chosen by lot. One was sacrificed. Over the other, the high priest confessed the sins of the people, and the goat was then driven into the wilderness, carrying those sins away. The text says this second goat is "for Azazel."
What Azazel means is still debated. Wikipedia summarizes four main readings: a word meaning "complete removal," a compound meaning "the goat that departs," the name of a rugged place in the wilderness, or the name of a demon or fallen angel. Merriam-Webster takes the demon reading as the likeliest.
Ancient translators leaned toward a description. The Greek Septuagint called the animal the goat "sent away," and the Latin Vulgate called it caper emissarius, the "emissary goat." According to Merriam-Webster, the idea rests on reading the Hebrew as 'ez 'ozel, "goat that departs."
William Tyndale followed that tradition in 1530, when he translated the first books of the Bible into English. He wrote "(e)scape goat," a goat that escapes. "Scape" was simply a short form of "escape," as in the word "scapegrace." Tyndale had coined a new English word from a disputed Hebrew one.
For almost three centuries, "scapegoat" meant the ritual goat and little else. Etymonline dates the modern sense, a person blamed or punished for the faults of others, to 1824. The verb, "to scapegoat" someone, came later. Etymonline dates it to 1884, while Merriam-Webster gives 1943, so the dictionaries disagree on when it took hold.
The meaning has also flipped in an interesting way. In Leviticus, the goat escapes: it walks away alive while its partner dies. In modern use, the scapegoat is the one who suffers. The word kept the animal and the blame, but lost the escape.
Other cultures had similar rites. Wikipedia notes the Greek pharmakos, a person expelled from a city in times of plague or famine, and comparable rituals in texts from ancient Ebla.