[5] Peadar's mother, Katie née McGuinness (1859/60–1907),[6] was from Rathmaiden, Slane, County Meath.

[9] He started at Belvedere College but played truant to escape beatings, so that his father ended his education and got him a job at a bicycle repair shop.

[10] His father died of pneumonia soon after, leaving Peadar to support his mother and five younger siblings.

Subsequently, theatres and the state broadcaster began playing the anthem at the end of performances, and Kearney prepared to take legal action to demand royalties, obliging the state to acquire the copyright in 1934 for £980 (half each to Kearney and the heirs of Heeney, who had died).

Other well-known songs by Kearney include "Down by the Glenside", "The Tri-coloured Ribbon", "Down by the Liffey Side", "Knockcroghery" (about the village of Knockcroghery) and "Erin Go Bragh" (Erin Go Bragh was the text on the Irish national flag before the adoption of the tricolour).

[19] Brendan Behan was in prison when Kearney died, and was refused permission to attend his funeral.

In a letter to Kearney's son, Pearse, he said, "my Uncle Peadar was the one, outside my own parents, who excited the admiration and love that is friendship.

"[20] Famed Irish sculptor and artist James Power did a portrait of Kearney in 1962 and is currently in the Kilmainham Gaol Museum.

[21] In 1957 his sister Margaret's son, Seamus de Burca (or Jimmy Bourke), published a biography of Kearney, The Soldier's Song: The Story of Peadar Ó Cearnaigh.