The Kingdom of Ireland (Early Modern Irish: Ríoghacht Éireann; Modern Irish: Ríocht na hÉireann, pronounced [ənˠ ˌɾˠiːxt̪ˠ ˈeːɾʲən̪ˠ]) was a dependency of England from 1542 to 1707, and subsequently Great Britain from 1707 to 1800. It was ruled by the monarchs of England and then of Great Britain in personal union, and was administered from Dublin Castle by a viceroy appointed by the English king: the Lord Lieutenant of Ireland. By the late 17th century, the state was dominated by the Protestant Anglo-Irish minority, known as the Protestant Ascendancy. The Protestant Church of Ireland was the state church. The Parliament of Ireland was almost exclusively Anglo-Irish. From 1661, the administration controlled an Irish army. Although formally a kingdom in personal union on equal footing with England and later Great Britain, for most of its history it was de facto a dependency with a viceroy sent as an envoy from London. This status was enshrined in the Declaratory Act 1719, also known as the Irish Parliament Act 1719.
The territory of the kingdom comprised that of the former Lordship of Ireland, founded in 1177 by King Henry II of England and the English Pope Adrian IV, after the Anglo-Norman invasion of Ireland. By the 16th century, the Pale, the area of effective English rule, had shrunk greatly; most of Ireland was held by Gaelic nobles as minor principalities notionally subject to London but independent in practice. By the terms of the Crown of Ireland Act 1542, Henry VIII of England became "King of Ireland", theoretically elevating Ireland to coequal status with England as a kingdom in personal union. There followed an expansion of English control during the Tudor conquest. This sparked the Desmond Rebellions and the Nine Years' War. The conquest of the island was completed early in the 17th century. It involved the confiscation of land from the native Irish Catholics and its colonisation by Protestant settlers from Britain. Most Catholic countries at the time did not recognise Protestant monarchs as legitimate kings of Ireland (or indeed of England), instead supporting the Jacobite government-in-exile from 1688 onwards.