Circa 60 AD (early Nero's reign) chattel slavery was still fundamentally fueled by frontier wars; the major contributors must have been then the Parthian wars, Britannia (it's the year of Boudicca's defeat) and the high Danubian border.
Greece was then by large a net consumer of slaves; if most (at least 2/3) of the Roman slaves had Greek names, that was just for fashion and not for their ethnicity (in fact, only 2-3% bore Semitic names). However, Greece was always the preferred source for expensive specialized professional slaves (eg, physicians).
Like for any other commodity, the maritime transport of slaves was faster, cheaper and far more efficient than by land; Brundisium and Ostia were the main ports of entry from Greece.
60 AD is also when the imprisoned Paul of Tarsus would have come to Rome and within the accepted range of dating for the Epistle to Philemon; may you be thinking about Onesimus or any other Christian-related story for your novel?
Thank you for the information.
I won't be using any sort of Christian-related story. This book is the first in a planned series of at least three. My main character here is the mother of the main character in the second book.
My novel's main character is a wealthy young woman from Thebes who is sold into slavery by her cousin when she runs away rather than marry him. He catches up to her and sells her as revenge. I was wondering if anyone knew of a book (or had the information) which tells where slaves would have departed from Greece. My best guess is the port of Athens. Also, since my main character is from Thebes, she will have to be transported by land for a certain portion of the journey. There will be only a few slaves at this point, perhaps 10, and are being taken to Rome intended to be sold as pleasure slaves and oddities(a hunchbacked man and a mentally disabled girl are among them). Would they have been chained together and made to walk, or would there have been wagons to make the journey faster? These are questions I haven't been able to answer through my research thus far.