Slavery in Ireland is an interesting topic. Although the standard image of
"slave" is male, i.e. a prisoner of war, the more common gender in early
Ireland was probably female. In isolated homesteads it was simply easier
and safer, or so it has been suggested. In any case, the two standards of
value in early Ireland are the set (3 set=1 1/2 milch cows) and a female
slave (cumal). The male slave (mug) is a common word, but not a unit of
value. Okay, already. For starters one might look at what Fergus Kelly
has to say about slaves in his book A Guide to Early Irish Law (1988) which
will help with the legal/social questions of who is and how one becomes a
slave. Also, there is the article by Paul Holm "The Slave Trade of Dublin,
ninth to twelfth Centuries" in Peritia, vol. 3 (1986):317-345. I hope these
references will be of assistance.
Dorothy Africa