John Baptist Sleyne (; – 16 February 1712) was Roman Catholic Bishop of Cork and Cloyne and Apostolic Administrator of the diocese of Ross, who was an enthusiastic patron of the Gaelic language and culture, and an advocate of the severely repressed Roman Catholic population, in Ireland during the early period of the Penal Laws. He was one of only two bishops to minister in Ireland at the end of the 17th century. Sleyne was very learned in languages and moral theology, and had traveled widely. He was known to and had interactions with kings, queens, popes and wider cultural and religious establishment throughout Ireland and Europe. Because Sleyne "remain[ed] in the kingdom contrary to the [penal] law", of the time, he went into hiding. He was eventually brought before the courts in 1698 and spent five years in prison in Cork Gaol. During his time as Bishop, both as fugitive and prisoner, Sleyne ordained many priests (estimated to be 38) and consecrated several bishops in Ireland. He was eventually exiled to Portugal, on 11 February 1703, where he was given shelter in the Irish Dominican Convento do Bom Sucesso, Lisbon. He died in Portugal on 16 February 1712, aged 74 years and is buried at the altar of the Sacred Heart in the Church of Nossa Senhora do Bom Sucesso.
There are many references to Sleyne throughout documents dating from the late 17th and early 18th centuries. Sleyne was sometimes referred to as Joannes Baptiste Mac Sleyne in the Irish college at Sorbonne, as Monsignor Giovanni Batista Sleyne in Rome, as João Baptista Sleyne in Portugal or as John Slyne in the records of the Grand Jury in his native Cork. In Gaelic literature, Sleyne was referred to as Eoin Baiste Mac Sleighne sometimes spelt as Mac Sleidhne. The molded capitals, at the top of the internal columns of St Colman's Cathedral of Cobh refer to him as Bishop Sliney.Fr John McCarthy, Administrator, Cobh Cathedral. 19 April 2018
The portrait of Bishop Sleyne, originally held at St. Isidore’s (the church of the Irish Franciscans, Rome) and now held at the [Cork and Ross Diocesan archives, is thought to be the oldest portrait in existence of any Catholic Bishop of Cork.
Early years, family and townland
Little is known about Sleyne's early life and family other than that he was born, in c. 1638, to John Sleyne in Ballymacsliney, Co. Cork and had two brothers and four sisters. (According to naming conventions of the 18th century, since both he and his father were both called John, he would likely have been the third eldest son in the family).
There are a number of candidates for location of the Ballymacsliney. Firstly, there is a townland of Ballymacsliney (Baile Mhic Shleimhne) near Midleton, Co. Cork that appears in the Down Survey (most probably misspelt) as BallmcGlinny within the Parish of Templencurrigg and the Barony of Barrimore. The landowner of the Barony of Barrimore was shown as Barry, David Fitz-David earl of Barrymore (Protestant) in both 1641 and 1670. (The intention of the Down survey was to measure out land held by Catholic Irish, that would then be forfeited and used to compensate English Merchant Adventurers and soldiers, for their support in the Cromwellian conquest of Ireland.) Secondly, there is also a town called Ballymacsliney, about 12 miles from Limerick. However, since Sleyne is mainly associated with Cork and in particular, East Cork, this could be discounted as being his townland. Thirdly, the name Ballymacsliney was applied to part of Maytown in Ballintemple parish, which was in the possession of the Mac Sleyne family. Records from 1616 and 1634 show that John Sleyne (probably Sleyne's father) held a Burgage at Cloyne, This suggests quite strongly that it is this latter third Ballymacsliney from which Sleyne came.
Sleyne's ancestors were of the FitzStephen family that had settled in the south east of Ireland after the Norman conquests (1170). Dominic O'Daly (sometimes called Donal or Daniel of the Rosary ) stated in his Relatio Geraldinorum that "Robertus Stephani, rater uterinus Mauritii filii Geraldi Magni, et germanus rater Regis Angliae a quo originem Stephensons ducunt, et Clann tSleighne omnes". Robert Fitzstephen (son of Stephen of Cardigan, and Nest ferch Rhys) was the first Anglo-Norman to invade Ireland, who along with Milo de Cogan, was granted 700'000 acres of land in Munster (about one third the area of Cork County) as compensation for his participation in the invasion. Fitzstephen claimed the (ancient) region of Olethan to the east of Cork city. In 1192, both Fitzstephen's illegitimate son Ralph Fitzstephen and Milo de Cogan were ambushed and killed near Imokilly, County Cork. Upon his death, Fitzstephen's lands fell to Raymond (le Gros) de Carew, his nephew and heir. Because de Carew died without legal issue (1198), the Fitzstephen's lands fell to Fitzstephen's half-sister's sons, Philip de Barry. De Barry's descendants thus became one of the largest landowners in the region and were created Earls of Barrymore in 1628 until their ultimate extinction in 1823. MacCotter suggests that Sleyne's family was descended, not from Robert FitzStephen, but his half-brother, William le Walys, who had accompanied him to Ireland. The Le Walys family took up residence in Rostellan in the late 12th century.
After the murder in 1333 of the Great Earl of Ulster, the third earl William de Burgo, and the subsequent decrease of English power in Ireland, the FitzStephen family, like most notable Anglo-Norman families of Munster and Connaught, became more and more Hibernicised. In a fashion, they became Hiberniores Hibernis ipsis or 'more Irish than the Irish themselves'. Anglo-Norman families spoke the Irish language, and assumed surnames like those of the Irish, by prefixing the word Mac (Gaelic for Son of, equivalent Old French fils or Fitz) to the Christian names of their progenitors. For instance, the De Burgos, in Connaught, assumed the name Mac William from their progenitor, William Fitz-Adelm De Burgo, while the Barrys of Cork took the surname of Mac Adam. Why the O' prefix (Irish meaning descendant) was not adopted is not clear. Similarly, the le Walys family of Rostellan took the patronym Mac Sleyney, thereby suggesting the existence of an eponym Sleyney le Walys (?). MacCotter notes 'James fitz Garrett Sleyney alias Stephenson, chief of his name in Imokellye' in 1554, which makes a connection between the name Sleyney and a person named Stephen (Sleimhne) who lived at a time much later than Robert Fitzstephen. Sleimhne was a rare Irish form of the Norman-French name Estievne (Stephen) brought to Ireland in the 12th century, other Irish forms being Stiabhna, Sdíomnha, Stiana, and Steimhín. In Mac Sleimne, the 'm' is an aspirated consonant denoted by a séimhiú or dot over the 'm' in Gaelic script or by letter 'h' following the 'm' in Latin script (that is Mac Sleimhne). 'h' was not a distinct letter in the Gaelic alphabet. Mac Sleimhne is used interchangeable with Mac Sleidhne, Mac Sleibhne, or Mac Sleighne (As a translation for the modern surnames Slyne etc.). The slender consonant 'gh' in Mac Sleighne or 'dh' in Mac Sleidhne is pronounced similar to the English 'y' sound, The slender consonant 'bh' in Mac Sleibhne or 'mh' in Mac Sleimhne is pronounced similar to the English 'v' sound. There are a number of references to Sleyne's ancestry (Mac Sleyney or Mac Sleighne as having derived from Rostellan, Cloyne, East Cork and CastleMacSleyney (?) O'Donnchadha writes "Is ag Mac Sleighne do bln Ros Stiallain agus Caislean Mic Sleighne, agus iomad d’aitibh eile i nlbh MoCoille, gur hionnarbadh iad le foirneart Gearaltach". The MacSleyney family held an estate at Rostellan, in Cloyne, composed of 1 carucate of plowland (120 acres), and 40 acres of woods at Cuilbane, when it was sold to John FitzEdmond Fitzgerald in 1565. We read that "In 1565, Gerald Fitz James McSleyney, Captain of his nation in Imokilly and true Lord of Rostellan, sold unto John FitzEdmond James de Geraldinis his manor of Rosteilan." The same Gerald MacSleyney (1568) and another David MacSleyney (1584) are mentioned among the County Cork Elizabethan pardons of the late 16th century. MacCotter refers to the Caislean Mhic Sleighne towerhouse at Rostellan.
Sleyne had two nephews, with surnames Slyne, each of whom was a priest during the early Penal times. It is not known if they were cousins or brothers of each other. One nephew, John Slyne was later Parish Priest of South Parish, Cork from 1752 until his death on 16 June 1759. He lived at Cove Lane, which is now Douglas Street in Cork. The second nephew, Bartholomew Slyne (B.Law), was enrolled as "priest of the province of Munster" at College Des Lombards community of Irish priests and seminarians in Paris and on 13 January 1723, was assigned the role of steward of a period of 2 years. Both nephews were imprisoned in Cork Gaol for reasons which will become apparent below. It is also reported that Sleyne had two nephews or cousins residing in Lisbon by the names of John and Mathew de Nort. (Could these be pseudonyms for his two nephews John and Bartholomew?)
Religious education in Sorbonne and early career
Sleyne was educated at the Sorbonne, Paris where he received a Master of Arts (1661), a Bachelor in Theology (1665) and a Doctorate of Divinity (1670), during which time, he became professor at the Sorbonne. At the age of 24, Sleyne was ordained priest by Andrew Lynch, bishop of Kilfenora (1647–1681) at Rouen on 27 Mar. 1663, by special privilege of Apostolic Indult because of his youth (assumed to be 23 years]). Sleyne returned to his native diocese of Cloyne where he was elected protonotary and dean of the cathedral. He later was made Vicar General of Killaloe by John O’Malony II, bishop of Killaloe (1671–1689). He was a member of the Order of St. Augustine (O.S.A.) and was administrator in commendam and last Prior of Ballybeg Priory of St. Thomas à Becket, which had been founded by Phillip de Barry in 1229 for the Canons Regular of St. Augustine.
In 1676, Sleyne went to work at the Propaganda Fide (Congregation for the Propagation of the Faith) in Rome, through which he petitioned for an appointment to the vacant diocese of Kerry (Ardfert). He was anxious to come "to the aid of the afflicted Catholics of Ireland". In Rome, Sleyne received high profile appointments, namely Professor of Moral Theology in the College of Propaganda Fide for 12 years, as spiritual director of the Ursuline nuns and as Roman agent for Peter Creagh, bishop of Cork and Cloyne (1676–1693). Some materials relating to Sleyne's time in the College Of Propaganda Fide, are held at the Franciscan Library, Killiney, Dublin. These were moved there from St Isidore's in 1873, when Rome was under threat of capture and destruction by the newly created Italian government.
In 2022, a portrait of a younger John Sleyne was presented by Taghg Doran on permanent loan to Cloyne Catholic Diocese. Before coming into private ownership, the 300-year-old portrait, was, for many years, held at Holy Cross Seminary, Clonliffe Dublin. It is believed that this painting is one of the oldest portraits in existence of an Irish Bishop, and is described by the current Bishop Crean as a welcome contribution to collection of Cloyne Diocese.
Fugitive during penal times