Select O'Reilly Surname Genealogy

Here are some O'Reilly stories and accounts over the years:

The O'Reillys at Cavan

By the late 1300's the O’Reillys had secured their land and moved their seat from Clogh Oughter Castle to Tullymongan Hill.  The castle they built there attracted settlers and a new town grew up in the hollow beneath Tullymongan Hill and the surrounding hills.  No one gave the town a name.  It was simply known as an Cabhan, Gaelic for “the hollow.”  To English ears the “'bh” sounded like “v” and so the name Cavan emerged. 

The O’Reilly Chief or Breifne was known simply as "The O'Reilly" in line with Celtic tradition.  The ancestral inauguration site of the Chief was at an ancient stone circle on Seántomon Hill three miles northeast of Cavan town.  The stones were fondly known as the fingers of Fionn McCool, a legendary Celtic hero.

Myles the Slasher and His Progeny

Myles O'Reilly, better known as Myles the Slasher, led the Irish resistance to the English during the 1641 rebellion.  For a time the whole of Cavan fell to his insurgents and Myles defeated a Scottish army under General Munro at the battle of Benburb.  But the Scottish fought back and Myles died in 1644, bravely standing up against their cavalry on the bridge at Finea. 

His son Colonel John Reilly lived at Baltrasna in county Meath and was said to have been the first member of the sept to drop the "O" prefix from the name.  He raised a regiment of dragoons for King James and served in the Jacobite army in the Williamite war.  He was allowed to keep his lands after the war was lost and he died at Batrasna in 1717. 

John left a son, Thomas, who was the father of Alexander or, as he became, Alejandro O’Reilly in Spanish service.

Count Alejandro O'Reilly

Alejandro O’Reilly from Baltrasna in county Meath had fought for Spain with the Irish Brigade.  He rose in Spanish ranks to become a Field Marshal, Governor of Madrid, Captain General of Andalusia and Governor of Cadiz. 

In 1769, he was dispatched to New Orleans with a strong military force to put down a popular uprising.  His affability allayed all suspicion and, after checking out the leaders, he invited them to a reception where he had them all arrested.  Five were put to death and the others were imprisoned in Havana.  That put an end to the rebellion. 

Count O’Reilly's rule in Spanish America was regarded as liberal and enlightened.  His descendants have been in Cuba for two centuries where, as the Counts of Castillo and Marquis of San Felipe y Santiago, their lineages can be found in the archives of  Havana.

Reilly and O'Reilly

Today it is O'Reilly more in Ireland, Reilly more outside.  The table below shows the approximate numbers:

Numbers (000's)

John Riley and the San Patricios

The San Patricios were a group of Irish-Americans who, during the Mexican War of the 1840’s, deserted the US Army to fight for the Mexican leader Santa Anna.  Their reasoning was twofold - they felt that they suffered discrimination by non-Catholic members of the American army and they also disapproved of the treatment of Mexican civilians, priests and nuns during the war. 

John Riley led the San Patricios in five major battles against the Americans, ultimately establishing his unit as a force to be reckoned with.  To this day, the flag of the San Patricios continues to fly in his hometown of Clifden in county Galway and a sculpture stands there in honor of John Riley and the men who served under him.

Andrew and Michael O'Reilly

Andrew and Bridget O’Reilly from Cork fled Ireland during the potato famine in the early 1850’s and made it with their three children to Canada.  The 1861 Canadian Census has them living in Halliwell township, Ontario.  Their son James moved across the border to Faribault, Minnesota and that was where Andrew and Bridget were buried in 1888 and 1889. 

It was thought that Andrew had a brother named Michael.  But nothing more was known about him. However, Chip Hutchinson, a great great grandson of Michael, managed to track down Andrew’s descendant Bill in 2008, thereby reuniting the two sides of the family.

Reader Feedback - Andrew and Michael O'Reilly

Would like to have a contact address for Chip Hutchison, descendent of the Andrew and Michael O’Reilly family.  I suspect Chip’s great great grandfather and my great great grandfather may have been brothers or some other close relation.  

Please share this email with Chip, along with my email address.  Thank you so much.

Dean O’Reilly in Oregon

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