Aramaic—the language of parts of the Bible, most of the Talmud, and much other Jewish religious literature—is still spoken today, although it is now in danger of extinction. But it was once the language that united the Middle East, as John McWhorter writes:
The Aramaeans—according to biblical lore named for Noah’s grandson Aram—started as a little-known nomadic group. But . . . by the 11th century BCE they ruled large swaths of territory in Mesopotamia, encompassing parts of modern-day Iraq, Syria, and Turkey—including, for a spell, the city of Babylon itself. . . . In 911 BCE, the Assyrians, who spoke a language called Akkadian, ousted them. But the Assyrians unwittingly helped the Aramaeans’ language extinguish their own.
Namely, the Assyrians deported Aramaic-speakers far and wide, to Egypt and elsewhere. The Assyrians may have thought they were clearing their new territory, but this was like blowing on a fluffy milkweed and thinking of it as destruction rather than dissemination: the little seeds take root elsewhere. Aramaic had established itself as the language of authority and cross-cultural discourse in Babylon and beyond, and with language as with much else, old habits die hard. People were soon learning Aramaic from the cradle, no longer just in one ruling city but throughout the Fertile Crescent stretching from the Persian Gulf through northern Arabia to the Nile. Even the Assyrians found it easier to adjust to Aramaic than to impose Akkadian. . . .
Here is also why Jesus and other Jews lived in Aramaic, and why portions of the Hebrew Bible are actually in Aramaic. The two languages are part of the same Semitic family, but still, when the book of Daniel switches into Aramaic for five chapters because Chaldeans are being addressed, it’s rather as if Cervantes had switched into Italian in Don Quixote for the tale of the Florentine nobleman. So dominant was Aramaic that the authors of the Bible could assume it was known to any audience they were aware of.