A local legend tells that on leaving Enniskillen, St Patrick remembered that he had left a manuscript after him there. He instructed his servant to "turn right", to return to retrieve his manuscript. The place thenceforth became known as An tIomp· Deiseal, "the right-hand turn". In his Dictionary of Ulster Place-Names, Patrick Kaye gives the pronunciation of this as "an chumpoo jeshel". It was rendered Tempodessell in 1622 but subsequently became Tempo. It is a town in the Co Fermanagh parish of Enniskillen.
In 1876, Tempo House was the residence of Sir William Emerson Tennent, whose 2,048 acres there was the largest Tennent holding in Ireland as noted by Owners of Land of One Acre and Upwards. Others bearing this surname had holdings in counties Dublin, Wicklow, Tipperary (1,875 acres at Mobarnan, Fethard), Antrim, Down, and Tyrone. Those in Ulster spelt the name Tennent while those in the rest of the country rendered it Tennant. There is but a single Tennent in current telephone directory entries for the whole island, with 21 Tennant south of the Border and 30 to its north.
The Penguin Dictionary of Surnames gives this as Scottish, meaning "the holder of a tenement (which in those days wasn't a tall block of slummy apartments)". Tener was a variant, having 6 entries in The Phone Book of Northern Ireland. Teners noted in Owners were Hampton E., John Kinley, and the Reps of Anne, with most of its 1,000 Co Tyrone acres at Moree, Dungannon. Richard Tener, listed at a hearing in Carlow in the Justiciary Rolls in 1311, is thought by the compiler of the index to the Rolls to possibly be Toner).
Our first sighting of this name is Thomas Tennant, one of the two Dublin sheriffs, in 1678. In 1790 Charles Tennant, merchant, Wine Tavern Street in Dublin, made his will. Among his belongings and interests were houses in Pill Lane, Patrick Street, Dirty Lane near Dame Street, one at the corner of Wine Tavern Street and Merchants Quay, one lately erected in Dame Street, and another at the south side of Thomas Street. In the Co Dublin parish of Kilsallaghan he owned land and property in Coolerath (228 acres and 20 acres Common), Chapellmidway, and Corrstown. And much more. To his son William he bequeathed his interest in the house and tan yard in Mill Street, and to his grandson Charles, £30.
The following year his brother Edward Tennant, linen draper, Pill Lane, made his will. "To his dearly beloved wife Sarah Tennant all his worldly substance, and house in Bolton Street, for life and then to his nephew Edwd. Tennant. To his brother Chas. Tennant his best case of pistols, and to his nephew Wm. Tennant his plate-mounted sword". E. Tennent, Esq., attorney, Summer Hill Parade, noted in the 1837 Dublin Directory, was probably a descendant of the above. Among the subscribers to Lewis`s Topographical Dictionary of Ireland (1837) there was a single Tener who resided at Moree, Dungannon, Co Tyrone.
There were five Tennents, of which four resided in Belfast. Tennent Street in Belfast is presumably named for this family.
And it was in Belfast's Barclay's Tavern, on April 1st, 1791, that those present at a meeting there resolved "to form ourselves into an association to unite all Irishmen to pledge themselves to our country". In October they founded the Society of United Irishmen, one of that group being Presbyterian, William Tennent.
He had also been present at a meeting that founded Belfast's second newspaper - the Northern Star, and also was on the committee that re-launched the Harp Society in 1791. George Tennent and Robert Simmons were delegates from Belfast who met the Dublin United Irish leaders in Dublin in 1795. That same year his younger brother John was one of a delegation of 30 who presented Ulster's case for a rising at a meeting in Dublin. They were overruled. R. and R. J. Tennent were among persons attending Irish language classes in Belfast in 1819.
Presuming that all the Tennents were some way related, a divide eventually came between the cultural and the political and economic.
James Emerson Tennent opposed Daniel O Connell`s 1834 proposal that the Act of Union should be abolished, in the belief that the Union greatly contributed to Belfast's increasing prosperity. R. J. Tennent was a Belfast MP from 1847 to 1852, and the seconder to a 1912 resolution of the Committee of Unionist Clubs voicing concern about "our Unionist cause" was R. Tennent Esq.
The rare Louth/Meath surname Tenanty, despite its appearance, is almost certainly a different surname.