Peter Tremayne, Our Lady of Darkness (Signet Mysteries, 2002)
Ireland has suffered so much from religious strife that it is easy to forget that it is one of the few places converted to Christianity peacefully. My Frankish ancestors were baptized at spear-point; my Irish ones welcomed Patrick, Palladius and the rest open-heartedly. The Church of Patrick and Brigid owed much of its success to its ability to adopt and adapt what was good in Irish society while introducing Christian beliefs and values. (The Church of Rome was never good at that, as witness the Frankish-inspired insistence on imposing the Latin liturgy and eliminating the vernacular, but I digress.)
In this world of harmony between Church and Society walks Sister Fidelma, a religieuse yet also a dálaigh of the Brehon courts, highly-educated daughter of one king and sister of another.
It is the middle of the 7th century, and the harmony is breaking down. Roman influences are spreading through Ireland. Even Fidelma counts as her closest friend Eadulf, a Saxon monk. When he is accused of a hideous crime, Fidelma races to save him from the punishment due to be meted out under the Roman Penetentials, a harsh system which would replace the gentler Brehon laws if the Roman church Eadulf serves won out.
On the other hand, Our Lady of Darkness skillfully weaves murder, sexual misconduct, vengeance, greed and a number of other deadly and venial sins. The plot keeps twisting till the very last paragraph. When I found out who the chief villain was I was disappointed, as I would rather it had been someone else, but all the clues were there in plain sight -- a hallmark of a well-written mystery.
Sister Fidelma is a refreshing heroine, one who reminds us that strong, well-educated women have been around since well before the 21st century. She's still very arrogant and intolerant, but she has grown over the course of the series. If you're interested in strong heroines, or in the earliest days of the introduction of Christianity to Ireland, you may enjoy Juilene Osborne-McKnight's Daughter of Ireland.
On the negative side, Tremayne does rather harp on the subject of Roman Catholicism versus Celtic Catholicism. The Roman Church surely can't have been as totally evil, or Irish society as idyllic, as he tries to suggest. The cavalry arrives far too fortuitously (somewhat after the nick of time), and there's a bit of deus ex machina about the way the political situation is resolved, for my tastes.
Peter Tremayne is the pseudonym of Peter Berresford
Ellis, a Celtic scholar.
He was born in England, but his father was Irish and his mother Breton.
He has written prolifically, both under his own name and as Peter Tremayne,
producing scholarly works as well as novels and short stories.
Green Man has also reviewed Absolution by Murder and Smoke In The Wind.
An excellent Web source on Sister Fidelma