McCathy History, Family Crest & Coats of Arms
The many Irish surnames in use today have long rich histories behind them. The name McCathy originally appeared in Gaelic as Mac Carthaigh, which is derived from the word "carthach," which means "loving."
Saint Carthach the Elder (d. 580?), appears in "the 'Felire' of Engus the Culdee (10th cent.) with the epithets of royal and Roman attached to his name. This is generally interpreted to mean that he was of royal ancestry, and had travelled to Rome [cf. Cainnech, Saint]. From the 'Vita Kierani' (Bollandist A. SS., March, v. 395) we gather that he was the grandson of Angus, king of Munster, who would seem to be the king whose death is recorded in the 'Four Masters' under the year 489. Colgan, however, noting that he was the brother of St. Cuanna, quotes from an old genealogy to show that he was the great-grandson of Neill of the Nine Hostages, who died about the year 405. In the 'Vita Kierani,' St. Carthach appears, before the death of St. Patrick, as one of St. Ciaran of Saighir's young disciples." 
Saint Cathach the Younger (d. 636) also called Mochuda, was "the founder of the famous monastery at Rahen, and bishop of Lismore, was the son of Finnall (Annals Four Masters, sub an. 631). According to his legendary life, which, however, seems to have preserved much that is historical, he was born in Kerry, of the race of Fergus." 
Early Origins of the McCathy family
The surname McCathy was first found in County Kerry and much of County Cork, in the area formerly known as Desmond. One of the oldest and most important of all Irish families, the MacCarthy family claim descent from Oilioll Olum, the 3rd century King of Munster who gave the region of Desmond to his son Eoghan after his death. Eoghan's descendants were known as the Eoghanacht, and the surname MacCarthy is derived from Carthach, an 11th century lord of this group who was killed when the Lonegans set his house on fire.
They were settled at Carrignavar where they were the Lords of Eoghannacht and Diarmod MacCarty Mor swore fealty to King Henry II thereby retaining his estates in Cork. Innumerable members of the family have been important in Irish history, especially those with the forenames Fineen, Florence or Justin, beginning with the Fineen MacCarthy who vanquished the Geraldines in 1261.
Several branches of the powerful MacCarthy sept existed, including MacCarthy Reagh, who held a family seat at Carbery in West Cork, and the Muskerry MacCarthys, who were based in the barony of Muskerry in that county. MacCarthy Mor of County Kerry, long thought to be extinct, has only recently been proven to still exist.
The McCarthy Reagh branch rose to become the Princes of Carbery in what is now southwestern County Cork in the 13th century. It is generally thought that Donal Reagh MacCarthy, the 5th Prince of Carbery, a quo MacCarthy Reagh, son of Donal Glas was the first to use Reagh is his surname. From this early listing, each subsequent prince continued to use Reagh in one form or another. As far as the early princes are concerned, we know very little. However from Finghin MacCarthy Reagh, the 8th Prince of Carbery from 1477 to his death in 1505, a solid genealogy has been determined.
Early History of the McCathy family
This web page shows only a small excerpt of our McCathy research. Another 127 words (9 lines of text) covering the years 1446, 1646, 1455, 1492, 1492, 1490, 1640, 1628, 1594, 1665, 1694, 1668, 1734, 1698, 1769, 1733 and 1734 are included under the topic Early McCathy History in all our PDF Extended History products and printed products wherever possible.
McCathy Spelling Variations
Irish names recorded during the Middle Ages are characterized by many spelling variations. This preponderance of variations for common names can be explained by the fact that the scribes and church officials that kept records during that period individually decided how to capture one's name. These recorders primarily based their decisions on how the name was pronounced or what it meant. Research into the name McCathy revealed many variations, including MacCarthy, MacCarty, MacArty, MacArthy and others.
Early Notables of the McCathy family (pre 1700)
Notable among the family name at this time was Blessed Thaddeus McCarthy (c. 1455-1492), an Irish ecclesiastic who never ruled his see, Bishop of Ross, Ireland in 1492 and Bishop of Cork and Cloyne in 1490, his feast day is 25 October; and Charles MacCarty (Cormac Oge McCarthy), (d. 1640). He was from the ancient line of Dermot McCarthy, King of Munster, and was created the 1st Viscount Muskerry in 1628. His motto was "Forti et fideli nihil difficile, " which translates as "to the strong and faithful, nothing is...
Migration of the McCathy family
Suffering from poverty and racial discrimination, thousands of Irish families left the island in the 19th century for North America aboard cramped passenger ships. The early migrants became settlers of small tracts of land, and those that came later were often employed in the new cities or transitional work camps. The largest influx of Irish settlers occurred with Great Potato Famine during the late 1840s. Although the immigrants from this period were often maligned when they arrived in the United States, they provided the cheap labor that was necessary for the development of that country as an industrial power. Early immigration and passenger lists have revealed many immigrants bearing the name McCathy: Daniel McCarty, who came to Boston in 1742; David McCarty, who settled in Maryland in 1755; Alexander McCarthy, recorded in the New York Colonial Muster Rolls in 1760.
The motto was originally a war cry or slogan. Mottoes first began to be shown with arms in the 14th and 15th centuries, but were not in general use until the 17th century. Thus the oldest coats of arms generally do not include a motto. Mottoes seldom form part of the grant of arms: Under most heraldic authorities, a motto is an optional component of the coat of arms, and can be added to or changed at will; many families have chosen not to display a motto.
Motto: Forti et fideli nihil difficile
Motto Translation: Nothing is difficult to the brave and the faithful