“Kushi’im” are mentioned in the haftarah for Kedoshim (this week), translated in our Etz Hayim humash as “Ethiopians.” In the haftarah on the eighth day of Pesah and again the other day on Yom HaAtsma’ut, we read that God will redeem “the other part of his people from Assyria, as also from Egypt, Pathros, Nubia…,” etc., with Kush being translated as “Nubia.” So where is/was Kush?
Kush (כּוּשׁ) was the eldest son of Ham, a son of Noah. His brothers were (and notice the place names) Canaan, Mitzraim (Egypt), and Put (Libya). Kush the empire existed inside a pocket-like half-loop of the Nile River, to the west of the Red Sea, nowadays in north-central Sudan reaching up into southern Egypt. Some have opined that the Garden of Eden was there, based on the rivers mentioned in Genesis. Kush was just one of several empires within Nubia, which was an elongated eggplant shaped region, which may or may not have extended south into what is now Ethiopia.
According to Livius.org, three great Nubian civilizations – Kushite kingdoms – were in the southern (“Upper”) part of the region (between the 3rd and 6th cataracts of the Nile, producing copper and gold), with capitals Kerma (early and middle Bronze Age), Napata (Iron Age), and Meroë (until Late Antiquity). Taharqa (possibly Tirhakah, 2 Kings 19:9 and Isaiah 37:9) was the Kushite king who solidly established the 8th century BCE empire, then running from central Sudan north to modern Israel. He was said to be the king (though it may have been Shabako) who sent an army to Hezekiah of Judah to resist the Assyrians under Sennacherib. There may have been two separate battles: it is disputed, but either way the Kushite army was both powerful and helpful.
Now, to Ethiopia, also formerly called Abyssinia. In ancient times, it was centered around Aksum, in what is now its north, 100 miles from the Red Sea coast. The early Greek writers used the term “Ethiopia” to delineate an empire between Ta-Seti in Lower Kemet (Egypt) and the confluence of the White and Blue Niles. Centuries thereafter, the name included a region encompassing southern Sudan, Ethiopia, Eritrea, Djibouti, Somalia, Kenya, Uganda, CAR, Chad, and more. Thus the overlap! The definitions of the boundaries have changed. The Buhen stela (in the Florence Museum) from the reign of Sety I (1294-1279 BCE) refers to the region as “Kas” and “Kash.” That was around the time when Moses took Tzipporah for his wife, to the ill-fated derision of his siblings for her Kushite heritage.
In those days, the people of Kush were known for their distinguished dark skin, the epitome of beauty. (Nubians were also known for their beauty.) The term Kushi today in Israel refers to black folks not necessarily from Ethiopia (an exodus worth another of these boxes), though the term is falling out of favor as it must be used with care, and always with the accent on the last syllable so as not to be perceived as dismissive or derogatory. (No reason even to notice, I say.)
All of this, of course, is not to be confused with the Kush Mountains in Afghanistan, home of Hindu Kush cannabis.