Scholars agree that the beginnings of Irish Christianity do not lie in Rome. In this study, Streit argues that a quite independent form of Christianity grew up in Ireland, which had a great influence on Dark Age Europe. Starting with the ancient, sun-oriented monumuments of the megalith age, he traces the evolution of an unbroken spiritual culture in Ireland from the time of stone circles and dolmens, through the Celtic era, into the period of the stone crosses of Irish Christianity. A detailed analysis of the symbols used in the megalithic period shows a highly evolved culture which was absorbed and developed by the Druidic Celts when they settled in Ireland in the centuries before Christ. This culture, in turn, found it natural to accept Christianity, which developed in a unique manner in such a spiritual climate. Early hymns and liturgical texts, combining the older nature practice with the new religion of Christianity, bear witness to this unbroken evolution.
Finally, Streit depicts the great missionary zeal of Christian monks like Columbanus, who established Celtic Christianity across Europe during the Dark Ages, until its final suppression by the increasingly powerful Roman Church in the 8th century. This study of the early history of Ireland is illustrated with black and white photographs, line drawings, maps and diagrams.