The term "bahro" comes to us not from D'ni, but from the Tehranee language. An offshoot, like D'ni, of the original Garternay civilization, the Tehranee people made it a practice to remove ahrotahntee, or book-worlders, from their native Ages and bring them back to Tehranee, then exploit them as slaves. The word "bahro" literally means "beast-person," indicating the scorn and disdain with which the bahro were viewed in Tehraneese society. (Book of D'ni, 198-201) The term may have been equivalent to and used to refer to the rehlyimah, an underclass of slaves who were entirely invisible to the Tehraneese society at large.
Though clear evidence has yet to be found, strong speculations exist that the D'ni civilization participated in this same enslavement during its history. Certainly, the records surrounding King Asemlef (DRC King Asemlef, para. 5) and the history of the Age Teledahn (Sharper's Journal, 2.15.00) would point to this conclusion. Whether the D'ni referred to their ahrotahntee slaves as "bahro" is unknown. The D'ni also used the word rehlyimah, in a wholly different context from the Tehranee, as a reference to a secret policing force. (DRC King Demath, para. 5-7)
Absues of ahrotahn peoples can be traced to the early history of D'ni. Shomat, the third king of D'ni, had a beautiful garden Age written for him that, unbeknownst to him, harbored an intelligent civilization, capable of communication, city-building, and armed defense. King Shomat bribed his brothers to destroy the native people; when that plot turned against him, he ordered that the Age's descriptive book be altered, against D'ni tradition, to eliminate the civilization. (DRC Shomat Translation, para. 15-27)
There has been a great deal of confusion between Shomat's Age and Eder Kemo. Even though the DRC left behind a notebook translation of Shomat's story on Kemo, the two Ages are not one and the same. In the words of the DRC, Kemo "was written during the 'Garden Binge' of the 8100's along with Eder Gira and numerous others... Though the Age was given to the D'ni general population by the Lords of the time, it was later replaced with a different Age" (DRC Age Restoration Report, Eder Kemo). It is unclear who drew the glyphs currently found on Eder Kemo.
Yeesha also makes frequent mention of the bahro, referring to them also as "The Least." Whether her terminology in turn refers to a rarely mentioned D'ni "sub-low" class, also known as "The Least," (DRC Class Structure, para. 9) is uncertain.