The material included in this volume comes from a variety of sources, including the archives of the diocese of Clonfert and that which was gathered in 1931 by an t-Athair Eric McFhinn, a noted polyglot and scholar of the diocese. Taken in conjunction with the Schools Folklore Commission's work a few years later, this material now has a value beyond even that which was foreseen at the time.

In June of 1922, in a singularly unhelpful exercise, some doughty Irishmen set off a landmine in the Public Records Office of the Four Courts. Thousands of old documents were destroyed, including the remaining censi from the nineteenth century and many of the Church of Ireland registers. Happily, just before this happened, Thomas T. O'Farrell had taken the time to type out extracts from the censi taken in Loughrea in 1821 and 1841 and they are also reproduced here in print for the first time.