On Wednesday 16 May 2018 I had the privilege of giving the 2018 Knox Lecture under the auspices of the Catholic Theological College, Melbourne. The lecture is held each year in honour of James Robert Cardinal Knox, fifth Archbishop of Melbourne. With 2018 marking the centenary of the end of the First World War I was requested to reflect on the way the Catholic Church in Australia related to and was affected by that war. I decided that in doing so I would explore the theme of “loyalty”, for it seems to me that during the First World War the issue of loyalty posed a significant challenge to the Catholic Church in Australia as it attempted to reconcile three sometimes competing loyalties: loyalty to the universal church, loyalty to the nation (a concept then ambiguous and in flux), and loyalty to Ireland. The text of my lecture “What price loyalty? Australian Catholics in the First World War” can be read here.