I can't answer on an organisational level in terms of the church hierarchy, however there were many individual priests who worked to support peace.

Peter Taylor in his book "Provos" describes one of the main secret back door go betweens linking the IRA and the Brits was a catholic priest. He is anonymous in the book and as far as I know he is still anonymous.

There are other examples of priests using their position in the community to try and calm things down.

• Fr. Edward Daly, later bishop Daly was involved in the civil rights movement, and appears in some of the iconic photos from Bloody Sunday. He has several autobiographies and books about the church in Derry that might give you the insight you are after...might, apologies but I haven't read them so can't say!

• During the hunger strikes it was a local priest who stepped in to work with families of the hunger strikes to end it all.

• Fr. Alec ried tried, and failed, to prevent the murder of two army corporals at a Republican funeral of people killed two days earlier at gun attack at another Republican funeral.

• Fr alec Reid was also working to build links behind the scenes between sinn fein and sdlp to help the peace process.

All these come from "Provos" by Peter Taylor, and are all individuals the book doesn't discuss the hierarchy, and so I can't help there!