"Anglo-Irish" is also used to describe formal contacts, negotiations, and treaties between the United Kingdom and Ireland. Some examples of this usage are the Anglo-Irish Treaty of 1921, the Anglo-Irish Agreement of 1985, and the Anglo-Irish Summits (as meetings between the British and Irish prime ministers are usually called).
In the United States, people who identify with the Ulster-Scots are sometimes called Scots-Irish or Scotch-Irish, while people whose ancestry can be traced to the Anglo-Irish refer to themselves only as Irish.
The "Anglo-Irish" landed elite replaced the Old English and Gaelic Irish Catholic aristocracies in the course of the 17th century as the ruling class in Ireland. At this time, they were usually called the "New English" to distinguish them from the Catholic "Old English," who were descendants of medieval Hiberno-Norman settlers. Under the Penal Laws that were in force between the 17th and 19th centuries, Roman Catholics in Ireland were barred from public office, military service, membership in the Irish Parliament, and from entering professions such as law and medicine. The lands of the old Catholic elite were largely confiscated in the Plantations of Ireland and their rights to inherit landed property were severely restricted. Those who converted to Protestantism were usually able to keep or regain their lost property.
The term "Anglo-Irish" was often applied to the anglicised Protestants who therefore made up the Irish professional and landed classes. A number of them became famous as poets or writers, including Jonathan Swift, George Berkeley, Oliver Goldsmith, Laurence Sterne, Bram Stoker, Oscar Wilde, W.B. Yeats, Cecil Day Lewis, and Bernard Shaw. Some, such as Edmund Burke, played an important role in British politics, while others, such as William Rowan Hamilton, G.G. Stokes, and Ernest Walton, were distinguished scientists. The Anglo-Irish were also represented among the senior officers of the British Army by men such as Arthur Wellesley, 1st Duke of Wellington (1769–1852); Field Marshal Lord Roberts, first honorary Colonel of the Irish Guards regiment, who spent most of his career in India; and Field Marshal Lord Gough who served under Wellington in the Peninsular War before rising to prominence by commanding the British army fighting the first Opium War in China. The famous composer Charles Villiers Stanford was Anglo-Irish.
The Anglo-Irish social class was often of mixed Irish-British ancestry and members usually identified themselves as Irish despite adopting many English customs. The more successful among them often spent their careers in Great Britain or in some part of the British Empire. In this sense, "Anglo-Irish" identified a social class. Playwright Brendan Behan, a staunch Irish Republican, famously defined an Anglo-Irishman as "a Protestant with a horse".
The term is no longer commonly used in this way since southern Irish Protestants, or Protestants of the Republic of Ireland as a group, despite retaining a certain distinctive identity, have been keen to stress their Irishness and loyalty to Ireland.
By 1700 the peerage of Ireland was composed mostly of Protestant families of British origin. One leading Anglo-Irish peer described his experience as one of the "Anglo-Irish" as being regarded as Irish in England, English in Ireland, and not accepted fully as belonging to either.
Among the most prominent Anglo-Irish peers are:
The Duke of Wellington, a renowned wit and master of the bon mot, is reputed to have responded to comments regarding his Irish nativity by stating that "being born in a stable does not make one a horse" (this was an often misquoted family joke about whether he had been born in Dublin, or at an inn between Trim and Dublin); as regards the ferocity of his Irish Regiments in the Peninsular Wars, that "I cannot say for certain if they will scare the enemy but they frighten the devil out of me.
As Wellington's male-line family surname had been Colley up to 1728, it is apparent that many families considered as "Anglo-Irish" after 1700 were in fact of earlier Gaelic or Old English origin, and had accommodated themselves with the changed realities after the Williamite War of 1689-91. These include William Conolly, Edmund Burke, the Dukes of Leinster and the Guinness family.
A number of Anglo-Irish peers have been appointed by Presidents of Ireland to serve on their advisory Council of State. Some were also considered possible candidates for presidents of Ireland, including: