After escaping to the United States, he became a prominent spokesperson for the Irish diaspora community and culture through his editorship of the Boston newspaper The Pilot, in addition to his personal writings and lecture tours.

Born in Dowth, County Meath, O'Reilly moved to his aunt's residence in England as a teenager and became involved in journalism before enlisting in the British Army shortly thereafter.

[1] In 1864, after returning to Ireland, O'Reilly joined the Irish Republican Brotherhood under an assumed name and was part of the group for two years until he and many others were arrested by the British authorities in early 1866.

In his final years of life, O'Reilly suffered from various health issues before eventually dying of an overdose in 1890 at his summer home in Hull, Massachusetts.

While O'Reilly was in the army, he grew disillusioned with British rule after witnessing first-hand government policies which he perceived as negatively affecting Irish Catholics.

[1] In 1864, O'Reilly joined the Irish Republican Brotherhood, then commonly known as the "Fenians", a secret society of rebels dedicated to an armed uprising against British rule.

On 10 October 1867 O'Reilly was placed in chains and marched off to the convict ship Hougoumont,[3] along with 61 other Fenian prisoners and 218 common criminals, for transportation to the British colony of Western Australia.

Midway through the voyage, O'Reilly and another prisoner John Flood, established a handwritten newspaper called The Wild Goose which contained poetry, stories and anecdotes from members of the ship's convict fraternity.

Seven editions were produced, and the single copy of the original set survives and is held in the State Library of New South Wales collection.

[4] O'Reilly quickly developed a good relationship with his warder Henry Woodman, and was appointed probationary convict constable.

)[6] While in Bunbury, O'Reilly formed a strong friendship with the local Roman Catholic priest, Father Patrick McCabe.

On 18 February 1869 O'Reilly absconded from his work party and met up with James Maguire, a local settler from the town of Dardanup.

[7]: 78 [a] O'Reilly hid in the dunes, awaiting the departure from Bunbury of the American whaling ship Vigilant which Father McCabe had arranged would take him on board.

The ship was sighted the next day, and the party rowed out to it, but the captain reneged on the agreement, and the Vigilant sailed off without acknowledging the people in the rowboat.

With him was a ticket of leave convict named Martin Bowman (alias for Thomas Henderson),[9] who had heard of the intended escape.

McCabe had arranged for the Gazelle to take O'Reilly only as far as Java, but adverse weather prevented the ship's finding safe passage through the Sunda Strait.

On 29 July the Gazelle met the American cargo vessel Sapphire on the high seas and O'Reilly changed ships.

O'Reilly quickly realised that New York did not offer any field for his ambitions and he was advised to move to Boston, which he did, arriving there on 2 January 1870.

[1] On August 15, 1872, O'Reilly married Mary Murphy (1850–1897), a journalist who wrote for the Young Crusader under the name of Agnes Smiley.

The third daughter, Agnes O'Reilly, went on to marry the philosopher William Ernest Hocking soon after he earned his PhD from Harvard University, where he would later teach.

In 1875 John Devoy sought O'Reilly's advice on how the Clan na Gael might rescue the six military Fenians serving time in Western Australia.

By the late twentieth century, most of his earlier work was dismissed as popular verse, but some of his later, more introspective poetry, such as his best-known poem, The Cry of the Dreamer, is still highly regarded.

In January 1887, a meeting was held to discuss his proposal and O'Reilly and fifteen others were appointed to a committee to investigate the feasibility of such an organization.

That evening he took a long walk with his brother-in-law John R. Murphy hoping that physical fatigue would induce the needed sleep.

On the morning of 10 August around 2 to 3 a.m. his wife woke up and found O'Reilly sitting in a chair, with one hand resting on the table near a book, and a cigar in the other.

O'Reilly's sudden death received an outpouring of grief and tributes from the Boston community and also globally, The Pilot published a full biography of his life in their 16 August edition.

On 20 June 1896 (nearly a week before what would have been his 52nd birthday), a multi-figure bronze sculpture of O'Reilly was unveiled, then-President Grover Cleveland gave a speech at the event.

Author and historian Francis Russell included an essay about O'Reilly in his 1987 book "The Knave of Boston & Other Ambiguous Massachusetts Characters".

[19] In 2002 an interpretative display was opened for John Boyle O'Reilly, in Western Australia on the Leschenault Peninsula Conservation Park, from where he escaped to the United States.

[21] In 1999 then-Western Australian opposition leader, Geoff Gallop, made an unsuccessful request to British Prime Minister and friend Tony Blair to grant O'Reilly a pardon.