This stirring history recounts how the Catholics of Ireland clung to the Holy Mass and the Real Presence through centuries of fierce persecution. From the age of St. Patrick through the brutal campaigns of Elizabeth I and Cromwell, the Eucharist remained the heart of a people willing to suffer imprisonment, exile, and martyrdom rather than forsake the altar. Drawing on vivid accounts of suppressed liturgies, hidden priests, and heroic lay faithful, this book reveals why the Mass became both the target of oppression and the source of unbreakable devotion. Their witness stands as a powerful summons to renewed reverence and fidelity in our own time.