The Borg are depicted as an amalgam of cybernetically enhanced
humanoid drones of multiple species, organized as an inter-connected
collective with a hive mind, inhabiting a vast region of space with
many planets and ships.
Now if they operate towards one single-minded purpose: to add the
biological and technological distinctiveness of other species to their
own, in pursuit of perfection, ...achieved through forced
assimilation, a process which transforms individuals and technology
into Borg, enhancing individuals by adding synthetic components; then
what do you do with some species who have religions like humans do?
http://en.wikipedia.org/wiki/Borg_(Star_Trek)