Review Article: Córus Bésgnai. An Old Irish Law Tract on the Church and Society. Edited by Liam Breatnach. Early Irish Law Series 7. Dublin: School of Celtic Studies. Dublin Institute for Advanced Studies. 2017. ISBN 978-1-85500-232-6

Liam Breatnach’s edition ofthe Old Irish law tex tCórus Bésgnai, a title that can be translated roughly as ‘customary system’, is the first new edition of this tract since it was printed in the Ancient Laws of Ireland in 1873. It forms the seventh volume of the School of Celtic’s Law Texts series. Córus Bésgnaiis a constituent part of the Senchus Már, the largest compilation of medieval Irish law. The core text is Old Irish, dating to c. 660–680 (Breatnach 2011: 19–42), accompanied by Old Irish glosses and Middle Irish commentary. Córus Bésgnaiis about societal relations in general, with a special focus on the Church in medieval Irish society. The author of the tract derives the Church’s special position from a more general consideration of the necessity of contractual relationships with reciprocal obliga-tionsin order for society to function