Orpen, Goddard Henry (1852–1932), lawyer and historian, was born on 8 May 1852 in Dublin, the fourth son of the five sons and three daughters of John Herbert Orpen, barrister, of Dublin, and Ellen Susan Gertrude, youngest daughter of Revd John Richards of Grange (latterly Monksgrange), Co. Wexford. For most of his childhood his parents' home was at 58 St Stephen's Green. He was educated at Tipperary grammar school and in 1869 entered TCD, where he displayed early academic aptitude, obtaining exhibitions and scholarships and being elected a foundation scholar. He graduated BA with first-class honours in 1873 and four years later was called to the English bar at the Inner Temple, London.
On 18 August 1880, in St Peter's church (Church of Ireland), Dublin, Orpen married Adela Elizabeth Richards (qv), the daughter and heiress of Edward Moore Richards, engineer and the landlord of Grange, Co. Wexford. Adela was Orpen's first cousin once removed, her great-grandfather and Orpen's grandfather being the Revd John Richards. They lived for two decades after their marriage at Bedford Park, Chiswick, London, with their daughter Lilian Iris (b. 1883) and son Edward Richards (b. 1884). Soon after their marriage Orpen began taking lessons in Irish in line with his passionate interest in Irish historical and antiquarian research, which gradually supplanted his languishing legal career. He translated and edited a French rhymed chronicle about the Anglo-Norman conquest of Ireland, entitled The song of Dermot and the earl (1892), the title which he gave it and by which it has since generally been known in English. He also translated Émile de Laveleye's Le socialisme contemporain (The socialism of today, 1884), to which he added a chapter on English socialism. After her father in 1900 transferred to Adela ownership of his estate, now renamed Monksgrange, the Orpens reluctantly left London to live there, enabling Orpen to devote his time fully to research and writing. His major work was Ireland under the Normans (vols 1–2, 1911; vols 3–4, 1920), which argued that the Norman invasion benefited the Irish, leading to advances in agriculture and trade.
Both before and after his death Orpen's work has been the subject of hostile criticism from those with more nationalist inclinations, starting with Eoin MacNeill (qv) in a series of lectures delivered in 1917. Despite his own eminence as a scholar of medieval Ireland, MacNeill resorted to unfair polemic in his attack on Orpen, caricaturing Orpen's account of pre-Norman Irish society and disregarding the more subtle nuances in his views of the English–Irish relationship. In this he has been followed by generations of other scholars and readers, overlooking the depth of Orpen's research, the perceptiveness of his interpretations, and the extent of his fieldwork on the archaeological evidence from the medieval period. Orpen took the study of Anglo-Norman Ireland out of the realm of vague antiquarianism and professionalised it. His standards were not those of 'the gentleman-amateur' as might be expected from his background, but of the twentieth-century 'scientific' historian, and he is therefore now widely regarded as the founder of the professional study of Anglo-Norman Ireland (Duffy). Perhaps the most striking evidence of the continued validity and relevance of Orpen's work is that his four-volume Ireland under the Normans has been twice republished in more recent years, in 1968 by Oxford University Press and in 2002 in a one-volume version by Four Courts Press.
Orpen was elected a member of the RSAI (president, 1930–32) and the RIA (1911), and contributed historical articles to their journals as well as to periodicals such as the American Historical Review (1913–14) and Cambridge Medieval History (1932, 1936). A lecture to the New Ross Literary Society was later published as New Ross in the thirteenth century (1911). He also contributed a major chapter on the medieval church to the second volume of Walter Alison Phillips's History of the Church of Ireland (1934). Though his literary work was recognised by an honorary doctorate from TCD (1921), he felt increasingly isolated as Monksgrange was targeted during the civil war and raided on several occasions. On religion he listed himself as an agnostic in the 1911 census. Orpen's final work was The Orpen family, a personal family history printed for private circulation in 1930. A portrait of Orpen by Seán O'Sullivan (qv) hangs in Monksgrange. Orpen died on 15 May 1932 at Monksgrange, and is buried alongside his wife Adela in St Anne’s churchyard, Killann. His very extensive papers, including correspondence, manuscripts and drawings, as well as records and papers of the Orpen family, are held at Monksgrange. Included there is a very large collection of his photographs, a skill in which he notably distinguished himself. A small collection of his correspondence is also held in the NLI.