Adomnán and the Law of the Innocent

…raising his holy hand, making the sign of the cross in the air saying to the beast, “do not advance any further; do not seize the man but quickly depart”. Then indeed the beast, at the command of this holy man, speedily flees trembling.

The dramatic passage above is from the Vita Sancti Columbae, the life of Columba, telling of his encounter with a huge beast with large teeth near Loch Ness1 The 7th of December this year is the 1,500th anniversary of his birth, and this year sees a series of events, including an exhibition by the RIA Library on the Cathach (available here). However this post is not about Columba but the writer of the passage above, Adomnán, who created a law which has been described as the “first Geneva Convention”. 

Adomnán was (from 679 to 704) the ninth abbot of Iona after its founder, Columba (Colum Cille). They were related; Adomnán’s father was five generations descended from Columba’s grandfather. He is first recorded in the annals in 687 AD as seeking the release of prisoners taken by in a raid by the half-brother of Aldfrith, king of Northumbria.  While there he presented his book De Locis Sanctis (On Holy Places) to the king. The book is an account of the travels in the Holy land of a Gaulish bishop Arculf, and the holy places there, supplemented by Adomnán’s research in the library at Iona. (Or possibly an account by Adomnán of the Holy Land and its holy places presented as an account of a journey.)

It was also here that Adomnán accepted the Dionysian reckoning of Easter over the traditional Irish Latercus (for more on computus, the Irish role in its development and the slow change to the Dionysian reckoning see this post). Iona did not follow him in this, however, but Adomnán stayed as abbot and wrote his Vita Sancti Columbae there, until his death in 704AD2.

Adomnán’s philosophical impact comes the statute he promulgated at the Synod of Birr in 697.  The Law of Adomnán (Cáin Adomnáin) has been called the “first Geneva convention” because it was framed to protect non-combatants in war. (Cáin refers to legislation or a statute, such as a king would pass in his tuath, in contrast to the Brehon law based on precedent.) Adomnán succeeded in getting the law (which he himself called the Lex Innocentium or Law of the Innocents) accepted, and guaranteed by forty clerical leaders, including all the most senior, and fifty-one secular leaders, including the High King, all other major Irish kings, plus two kings from Scotland. (The text of the law survives in late copies, available here from paragaph 28,  starting with the list of guarantors, with the provisions following.)  

This law was truly innovative in the Irish context. Fines were the normal punishment for crime, with fines set based on the injured person’s standing in society. King, lord, cleric and poet were high ranking, freemen and unfree were at the bottom. Striking a woman or child incurred a lesser fine again, since dependents of a man (wives, daughters living at home, sons not yet adult) normally had an honour price of half the man’s honour price. The currency in which fines were denominated was the cumal (a female slave or three milch cows).

While the system of fines had some advantages (for example, where fines would fall on relatives of a transgressor it gave people an incentive to curtail actions of family members), it also treated the same crime differently depending on the victim. The law viewed the striking of a poet more seriously than the striking of a freeman reflecting the inegalitarian and hierarchical nature of Irish society. It also meant that for the wealthy careless injury or killing of a low status person, especially a child or woman, bore a light penalty for them. 

There was an exception to the setting of honour price by status: all (male) children had the same honour-price up to the age of seven. Adomnán effectively widened the scope of this exception, leading to a wide degree of equality under the law when it came to punishing violent crimes against non-combatants, i.e. clerics, those under penance (who were not allowed use arms), women and children (including boys).

All adult men besides the exceptions given were both entitled and obliged to carry arms.  Ireland was a violent society: since there was no central authority to enforce law, direct action was often required to implement judgements, ranging from seizing of assets to outright warfare. Adomnán intended for his law to apply in all these contexts. 

The law gave women independent honor prices for the first time, with seven cumals (the same as a freeman) to be paid for a woman killed. This included what we would call cases of negligence today. Part of these fines were to be paid to Iona, meaning Iona was made a protector of women. If an woman was killed, even if there was no surviving relative, atonement could be sought. The new law gave women equal status with men in terms of the value of their lives. The law explicitly extends to women’s workplaces and servile women (i.e. slaves), acting as a broad protection against violence and death.      

Similarly boys not yet able to bear arms or not wishing to received increase protection, with a cleric or youth between seven and adulthood receiving an honour price of eight cumals. 

The three categories are drawn together for penalties for injury, with fines again going to Iona. It is made clear that all adults, man or woman, face these penalties. There is a change in terms of crimes that would face the death penalty such as murder, poisoning, arson and undermining churches: women will instead be set adrift in a boat with one oar, with God to chose her fate. (This suggests Adomnán viewed that such action by a woman might have extenuating circumstances that a judge might not learn, meaning judgement by God was appropriate.) 

This law not only brought a form of  central authority for violent crimes and a more equal valuing of the lives of women, children and men, but it was innovative on a broader scale. The tenth and eleventh century Pax Dei (Peace of God) movement has been widely recognised as the earliest example of legislating behaviour in warfare. The Lex Innocentum predates that movement by three centuries3.  

This milestone in Irish law “reflects Adomnán’s concerns with the preservation of peace and civil order and the protection of women” 4. James W. Houlihan. whose piece goes through the terms of the law in detail, suggests that the strange tale proceeding the text of the law itself perhaps reflects an encounter Adomnán had with the aftereffects of war on the innocent. He also points out that Adomnán’s  Vita Sancti Columbae, written around this time, includes four chapters in which Columba deals harshly with offenders against “innocents”. 

Further Reading 

“Cain Adamnain: An Old-Irish Treatise on the Law of Adamnan” from Fordham University Medieval Sourcebook. (link) – the strange tale that precedes the dry legal text gives an interestingly negative picture of the status of women in early Christian Ireland.  

“Adomnán: the man behind the milestone law” from The Royal Irish Academy (link)

Marie O’Dwyer (2015) “Cáin Adomnáin, 697: the Irish ‘Geneva Convention’” History Ireland Vol. 23, Issue 1. (link

J. W. Houlihan, (2019) “Lex Innocentium(697 AD): Adomnán of Iona – father of Westernjus in bello”, International review of the Red Cross (2005), vol. 101, no. 911, pp. 715-735. (link)


Featured Image: Stained glass window depicting Adomnán in Raphoe. Andreas F. Borchert/Wikimedia (CC BY-SA 3.0 DE)


  1. Vita Sancti Columbae, Liber Secundus, Caput 28. (from The Latin Library). My translation.
  2. Aidan Breen (2009). “Adomnán” in James McGuire, James Quinn (ed.),  Dictionary of Irish Biography. Cambridge, United Kingdom: Cambridge University Press. ( also online at RIA
  3. J. W. Houlihan (2019) “Lex Innocentium(697 AD): Adomnán of Iona – father of Westernjus in bello”, International review of the Red Cross (2005), vol. 101, no. 911, pp. 715-735.
  4. Breen
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