Irish Surname - Reilly
The surnames Reilly and O'Reilly are very popular in Ireland, being among the first dozen in the list. The name derives from the Irish O'Raghailligh, possibly meaning 'sociable tribe', a descendant of Raghallach, the grandson of Conchobhar, king of Connacht in the 10th century, and founder of the clan O'Connor.
The O'Reilly territory was around Lough Oughter in County Cavan and for centuries they were the most powerful sept in Breffny / Breifne. (The Irish word Breifne means "hilly country".) In the 10th century the territory of Breifne was divided into two sections, Breifne O'Rourke or West Breifne, and Breifne O'Reilly or East Breifne. In 1584, during the reign of Queen Elizabeth, Breifne O'Reilly was turned into a county and became County Cavan, named after its principal town. The seat of the O'Reillys was at Tullymongan Hill on the outskirts of Cavan town, their leader being chief of Breffny-O'Reilly and for a long time in the middle ages his influence extended well into Meath, Westmeath and Longford. Today the Reillys are primarily from Cavan, Cork, Longford, and Meath.
The sept were notorious for being extremely tough, determined, and often violent family. The legendary 17th century figure "Miles the Slasher" typified the fierce O'Reilly tradition. He was High Sheriff of County Cavan and distinguished himself as a commander in the ill-fated rebellion against the English to regain lost territory in the 1640's. He later had to flee Ireland and went to Spain but eventually ended up in France, where he died about 1660 and was buried in the Irish monastery at Chalons-sur-Marne.
In 1878 O'Reilly landlords possessed over 30,000 acres. The Franciscan Abbey of Cavan was founded by Giolla Iosa O'Reilly, and over the centuries there have been no less than thirty-nine O'Reilly abbots, while five O'Reillys have held the Primacy as Archbishop of Armagh, Primate of All Ireland.
In King James III's Irish army, Col Edmund O'Reilly's regiment of infantry included thirty-three officers and Col Mahon's regiment had sixteen officers called Reilly or O'Reilly. Many of these became Wild Geese.
The celebrated Count Don Alexander O'Reilly from County Meath had a distinguished military career, first in the Austrian service and then in the Spanish army. He ended his days as Governor of the French colony of Louisiana where he died in 1797.
The O'Reillys had a reputation as astute financiers and in the 15th Century, they devised their own coinage, hence a "Reilly" came to signify a coin of useful value.
In Griffiths Valuation c1850s, Reilly households outnumbered O'Reillys nearly 20-1. At that time the highest concentration of the name was 1759 Reilly households in Cavan and 579 in Meath.
In Ireland c1890 only 10% of the surname had the O’ prefix, but at the beginning of the 21st century there was a 60% usage of the O' prefix.
Edward O'Reilly (d.1829) published one of the first Irish-English dictionaries in 1817. In 1820 he compiled a chronological account of almost 400 Irish writers. His dictionary came too early to contain the phrase "the life of Reilly". The expression is said to have first appeared in a ballad composed about the time of the Crimean War (1854) by a County Westmeath doctor named William Nedley.
Thomas Devin Reilly (1824-1854) was a revolutionary Irish writer who was forced to escape from Ireland to New York in 1848 after charges were brought against him for a scathing article which appeared in the United Irishman. In America he went on to edit the New York Democratic Review and afterwards the Washington Union. He died suddenly in Washington on March 6, 1854, and was buried in Mount Olivet Cemetery.
The Fenian John Boyle O'Reilly (1844-1890) also made a name for himself as a journalist and writer in America. Because of his activities in the revolutionary movement against England, he was arrested in 1866 and sent to the convict settlement in Bunbury, Australia. He escaped in 1869 and settled back in Boston where he worked as a journalist. He continued to support the Irish revolutionary movement and became editor and part owner of The Pilot, one of the most influential Irish-American newspapers in the United States. He occupied a distinguished place in the literary society of Boston, wrote many poetical works, and also edited The Poetry and Songs of Ireland (New York 1889). As a novelist O'Reilly will be remembered as the author of Moondyne, a story of convict life in Australia which was published in 1880 and ran through twelve editions.
Egan O'Rahilly (1670-1726) was of a family long established near Killarney. He was an outstanding poet and regarded by many as one of the greatest of all Gaelic poets. He specialised in the genealogy of the leading families of Munster, glorifying them in his poems. During his lifetime, following William of Orange's suppression of the Irish, the old Gaelic order was swept away until there was no longer any place for Irish literature. O'Rahilly endured fearful poverty, but continued to write poetry until his death.
Coat of Arms
The Coat of Arms most associated with the family is a green shield with two gold lions rampant combatant, supporting a dexter hand couped at the wrist erect and apaumee bloody proper.
"Fortitudine et Prudentia" (Fortitude and Prudence)
Alternate Surname Spellings
Researching Irish Surnames
We have researched many sources for the origins of Irish surnames and extracted a fair representation of the origins of each. As there are many variations we have compiled a representative, but by no means exhaustive, selection.
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