Many early Irish first names were associated with particular families, ie, Corc with the (O) Moriartys or o Keeffes, and Coilean with the o Dempseys. Old Gaelic families did betimes give a son or daughter a "foreign" name, and de Bhulbh's Sloinnte na hEireann/Irish Surnames says that one chose to name a son Oitir, a Norse personal name. Oitir's son was Mac Oitir (son of Oitir), which in turn became Mac Coitir, and later anglicised (Mac) Cotter.
Annala Rioghachta Eireann/Annals of the Four Masters relates that in 916 Oitir and the foreigners went from Loch Dachaech to Alba; and in battle with Constantine, the son of Aedh, Oitir and his foreigners were slaughtered.
In 1142, the son of Mac Oittir, one of the people of Insi-Gall (the Hebrides), assumed the chieftainship and government of Dublin.
Of the 705 Cotter telephone entries south of the Border, 380 are in the southern 02 area, with a further 123 in the adjoining 06 area. There are three Mac Coitir entries. Cotter telephone entries north of the Border number 24. This surname has long been associated with Co Cork, though in medieval Ireland the MacCotters of Tipperary belong to an Ostman community of 300, perhaps around Roscrea.
A very wealthy member of this race was Reginald MacCoter "usurer" (Sheriff's Accounts for County Tipperary, 1275-6: Edmund Curtis (1934)). A hearing at Cashel on June 15th, 1308 concerned a dispute over land, and Reginald Mc Coitir was a named bailiff in the case. In 1318, Ricardo Mc Otyr was noted as vice-sheriff of Co Tipperary. Variously spelt, this surname is listed in 15 of The Irish Fiants of the Tudor Sovereigns (15211603). They were all in Co Cork - in Corrabally, Ringmeen, Carrigatoortane, Corkbeg, Coppingerstown, Barry's Court, Sarsfieldscourt, and Inchibacky.
A Census of Ireland circa 1659 lists Edmund Cotter as titulado in Ballinsperigge (Ballinsperry), Co Cork, with o Cotter among the principal Irish names in the barony of Barrymore in that county. Index of Irish Wills lists 13 Co Cork Cotter wills between 1661 and 1800, the earliest being that of Edmond Cotter, Ballinspaig, in 1661. Listed in King James's army was the Regiment of Dragoons of Col Sir James Cotter (1689).
In the course of the trial of one Patrick Hurley charged with a faked robbery, a list of gentlemen, against whom information was given, was produced, and on that list was Sir James Cotter. This man was executed in 1720, and some 20 poems were written in commemoration of this event.
Scriobhaithe Chorcai 1700-1850 (Breandan O Conchuir: 1982) lists nine poets/writers bearing the name Mac Coitir. Sir Seamus (1630-1705) resided at Ballinsperry. "Moreover, though the pre-1720 Cotters lived at Ballinsperry, near Carrigtohill, the larger of their estates in extent was at Rockforest, less than two miles from Killavullen (The Blackwater Catholics and County Cork Society and Politics in the Eighteenth Century by L. M. Cullen in CORK: History & Society). Ballinsperry, later to become Annegrove, appears to be Baile na Speire, "the town of the rock/mountain spur". James Cotter (1714-1770), son of Sir James (1689-1720), resided at Rockforest. He had forsaken the religion and politics of his forebears and was created a baronet of Ireland in 1763. Cotters were at Rockforest on Taylor & Skinners Maps of the Roads of Ireland (1778), and in the 1814 Directory.
Sir James Cotter MP was among the bankers in Parliament who took their lead from their aristocratic patrons and supported the 1800 Act of Union. Documents Relating to Ireland 1795-1804 wherein an "Account of Secret Service Money, Ireland, 1798", notes that in 1803 Sir James Cotter was in receipt of two payments, one of £17 1s 3d and another of £20 "for secret service in detecting, preventing or defeating treasonable or other dangerous conspiracies". Owners of Land of One Acre and Up- wards (1876) listed 12 Cotter holdings, 10 in Co Cork. The largest was the 3,783 acres of Sir James L. Cotter, Bart, Sunny Hill, Mallow. Rev George E. Cotter was at Rockforest of 916 acres, with a further 221 acres there in the hands of the Reps of H Cotter.
Thomas Cotter, Joseph Cotter, and Joseph's widow Sarah, were booksellers, printers, and publishers beneath Dick's Coffee House, Skinner Row, Dublin, from around 1700 to 1770.