Chamberlain (Chamberlane), Robert (d. 1636), Franciscan friar, theologian, and political activist, was probably born at Niselrath (later Rathneestin), in the parish of Tallonstown, Co. Louth. His father was Roger Chamberlain, and five of his brothers fought in the Nine Years War on the side of the Gaelic confederates. Robert, however, was not destined for a military career. After his early education in Ireland, he went to Spain. He graduated BA and in 1595–6 was in his first year of theology at the university of Salamanca; he completed a doctorate in theology there and was ordained priest in 1599. The precise date of his return to Ireland is unknown, but in June of that year he was reported to have written two letters on behalf of Hugh O'Neill (qv), 2nd earl of Tyrone. The following October, Lord Deputy Essex (qv) referred to him as employed from Rome and doubted if Tyrone would speak freely in Chamberlain's presence about peace negotiations. In January 1601 Sir Geoffrey Fenton (qv) referred to him as Tyrone's confessor, and the earl's decision to send Chamberlain to Spain at that time was interpreted by the English authorities as evidence of Tyrone's uncertainty about Spanish intentions, Chamberlain being ‘ex intimis consiliis with him’.
Chamberlain's close relationship with the earl of Tyrone endured until the latter's death in 1616. He seems to have acted as tutor in Spain to O'Neill's son Henry after 1601 and was present with him in Spanish Flanders in 1605. The following year he was reputed to be in London in disguise, gathering information for O'Neill, and in August he was granted a pension of 30 crowns a month by Philip III in recognition of his services to the army in Flanders and of his family's contribution in the Nine Years War, in which two of his brothers were killed. In 1607 he was again in Flanders, acting as a close adviser to Henry O'Neill. On 21 October of that year he met the exiled earls of Tyrone and Tyrconnell (qv) at Douai, and in February 1608 he departed to Spain as their emissary. That year also he was reputed to be in the process of preparing Tyrone's apologia for publication, and began his career as lecturer in sacred theology at St Anthony's College at Louvain.
On 7 February 1610 Chamberlain became a Franciscan novice, and the following year, around his fortieth birthday, he was professed as a friar. Roughly four years later, he seems to have begun to lecture in theology at the university of Louvain. He also continued his service to the earl of Tyrone, possibly again serving for some time again as chaplain to O'Neill. In July 1615 he appeared in Brussels with letters from Tyrone authorising him to forward and conclude Henry O'Neill's marriage to the daughter of Don Juan de Mancicidor, the private secretary of Philip III. His business was also reported to be the commissioning of Irish privateers to capture the shipping needed for an invasion of Ireland. By September 1615 he was reported to have returned to Rome.
In 1626 Chamberlain found himself in the eye of an ecclesiastical storm concerning the archbishopric of Armagh, which had just become vacant on the death in September of his fellow Franciscan and close associate Hugh Mac Cathmhaoil (qv). Essentially the same coalition of interests that had secured Mac Cathmhaoil appointment the previous April now attempted to have Chamberlain installed as his successor. He was the favoured nominee of the earls of Tyrone and Tyrconnell, of the infanta Isabella, of the nuncio in Brussels, and of the clergy of Armagh, who named him in their letter of recommendation sent to Rome. The testimonials on his behalf uniformly stressed his Ulster provenance, noble birth, academic distinction, and unblemished personal life. Revealingly, even those who opposed him conceded that he was both learned and virtuous. Their opposition thus centred on his links to the military exiles, which would make it impossible for him to reside in Ireland, the fact that he was a Franciscan, and his lack of pastoral experience. Since none of these factors had prevented Mac Cathmhaoil’s elevation, and since Chamberlain was recognised in Rome as the single strongest candidate, it seems probable that his personal reluctance to accept the position was the chief reason why he was passed over. The modesty of his character did not escape the attention of his contemporaries. It was noted of him, for instance, that he abhorred all honours and that, despite repeated invitations, he could never be prevailed upon to accept the guardianship of St Anthony's College. He died of natural causes at the convent at Louvain on 11 June 1636 (NS) and was buried there.
Chamberlain was multilingual. Despite his comprehensive mastery of Latin, Spanish, and English, Irish was probably his mother tongue. In that language he was generally referred to by the familial patronymic, Mac Artúir, and it seems highly probable that he was the accomplished Gaelic poet Roibeard Mac Artúir, who contributed to Iomarbhágh na bhFileadh (although Irish language scholars have pondered the question of whether Chamberlain's long time associate, Florence Conry (qv), may not have been the true author of some or more of the poems attributed to Mac Artúir). Mac Artúir's meditations in his poetry on the nature of a tyrant and of a true king are of particular interest in view of the fact that Robert Chamberlain was the author of one of the bluntest written descriptions of a Stuart monarch by any Irishman in the first half of the seventeenth century. In a secure private communication to Luke Wadding (qv), head of St Isidore's College in Rome, on 4 August 1628 Chamberlain declared that Charles I ‘non solum est publicus haereticus, sed etiam Catholicorum persecutor et seminator heresis’ (Jennings (ed.), Wadding papers, 266).
Chamberlain's chief fame on the continent was as a theologian. He was apparently the author of at least two treatises, ‘De scientia Dei’ and ‘De futuris contingentibus’, neither of which seems to have survived. Since he wrote a testimonial in favour of his colleague at the department of philosophy at Louvain in 1624, it seems probable that he was sympathetic to the theological positions of what was to be identified after 1640 as Jansenism.
Probably because so much of his literary output has been lost, Chamberlain is one of the more shadowy figures within the profoundly influential group of Irish Franciscans who centred on Louvain in the seventeenth century. Yet he was evidently one of the major figures within the group and among its most brilliant intellects. In particular the parallels between his career and Conry's, down to their entry relatively late in life into the Franciscan order, are startling. Chamberlain's close relationship with Hugh O'Neill is also noteworthy. That O'Neill was able to attract and maintain the services of such a devout and learned cleric throws light not only on the earl's character but also on the politico-religious context of Irish rebellion and catholic reform in the early modern period. Chamberlain remains most noteworthy, however, for the striking confluence in his career of three intermingling currents: political activism, theological scholarship, and Gaelic learning. His younger relative Arthur Brownlow (Chamberlain) (qv) similarly straddles several worlds.