Justiciar of Ireland

The chief governor was the senior official in the Dublin Castle administration, which maintained English and British rule in Ireland from the 1170s to 1922. The chief governor was the viceroy of the English monarch (and later the British monarch) and presided over the Privy Council of Ireland. In some periods he was in effective charge of the administration, subject only to the monarch in England; in others he was a figurehead and power was wielded by others.

"Chief governor" is an umbrella term favoured by eighteenth-century historians Walter Harris and John Lodge and subsequently used by many historians and statutes. It was occasionally used before then. Chief governors were appointed under various titles, the most common of which were:

Less common titles include procurator and gubernator, and the temporary title custos or keeper.

Sometimes individuals with different titles served simultaneously, in which case the order of precedence was: lieutenant > justiciar > custos > deputy (lieutenant) > deputy justiciar. The title "Deputy", and later "Lord Deputy", was originally applied to the resident deputy of a non-resident king's lieutenant, when the latter title was an honour bestowed on a favoured English noble. Latterly, such resident deputies were called Lord Justices.

Statute Law Revision Acts passed in the 1890s trimmed formulas such as "the Lord Lieutenant or other Chief Governor or Governors of Ireland" from older acts of parliament, standardising to "the Lord Lieutenant".

In Norman Ireland as in England, a chief justiciar combined executive and judicial functions. The judicial offices of Lord Chancellor of Ireland and Lord Chief Justice of Ireland later separated from that of the chief governor. In the fifteenth century, chief governors, especially the Earls of Kildare, began taking initiatives in the Parliament of Ireland contrary to the wishes of the English court. This prompted the passing of Poynings' Law in 1495 to make Irish laws subject to amendment and veto by the Privy Council of England. From 1569 to 1672, much of the land was under martial law and the Lord Deputy had regional deputies in the Lord President of Munster and Lord President of Connaught. From the Williamite Wars till the Constitution of 1782, the Lord Lieutenant was a British noble who came to Ireland only every two years, when Parliament was in session; his main role was to steer legislation through Parliament. Three ex-officio Lords Justices deputised in the Lord Lieutenant's absences.

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