wyvernfriend
Historical fails occasionally, the Norman invasion of Ireland happened in 1169, this is set in 1172, with the Norman invasion came their castle technology, so there would be no baileys or donjons in Irish possession until well after that time. The names also don't resonate well, in fact the heroine Carice Faoilin's name stuck a bit. The description of the High King as having a brutal reputation with few women who wanted to marry him (not really spoiler stuff here, this is all on the first page) belies history where he had 6 co-wives, which the annals condemn.
She would have been considered to have entered a form of marriage with Raine de Garenne under early Irish Law as well. see here and forced marriage was frowned on, although it probably happened. This is the society and assumptions she would have lived with, not modern law (again let's reference the fact that this was 3 years post-norman invasion and it wasn't until Elizabethan times that Brehon Law was properly enforced.)
The allergy stuff was interesting but missed a point, barley.