Briscoe is born in Dublin on September 25, 1894, the son of Abraham William Briscoe and Ida Yoedicke, both of whom are Lithuanian-Jewish immigrants. The original family name in Lithuania is believed to have been Cherrick or Chasen. His brother Wolfe Tone Briscoe is named after Theobald Wolfe Tone, one of the leaders of the Irish Rebellion of 1798. His father is the proprietor of Lawlor Briscoe, a furniture factory on Ormond Quay which makes, refurbishes, imports, exports and sells furniture, trading all over Ireland and abroad.
Briscoe is active in the Irish Republican Army (IRA) and Sinn Féin during the Irish War of Independence and accompanies Éamon de Valera to the United States. He speaks for the Sinn Féin cause at public meetings there and is adamant that being a “Hebrew” does not lessen his Irishness. He is sent by Michael Collins to Germany in 1919 to be the chief agent for procuring arms for the IRA. While in Germany in 1921 he purchases a small tug boat named Frieda to be used in transporting guns and ammunition to Ireland. On October 28, 1921 the Frieda slips out to sea with Charles McGuinness at the helm and a German crew with a cargo of 300 guns and 20,000 rounds of ammunition. Some sources cite this shipment as “the largest military shipment ever to reach the IRA” consisting of 1,500 rifles, 2,000 pistols and 1.7 million rounds of ammunition. On November 2, 1921 the Frieda successfully lands its cargo near Waterford Harbour.
In June 1922 during the Irish Civil War, Briscoe is involved in an incident with fellow anti-treaty IRA members who attack pro-treaty politician Darrell Figgis at his home. They enter the house and assault Figgis, cutting off his well-prized beard in the process. This traumatises Figgis’ wife Millie, who had been under the impression Briscoe and his fellow assistants had come to kill Figgis. In November 1924 Millie commits suicide, expressing in a suicide note that she was suffering from depression as a result of the 1922 attack. Figgis himself commits suicide in 1926.
In his biography, Briscoe recalls an incident of being recognised by a pro-Treaty opponent during the Civil War. He merely turns and walks away, confident that his enemy will not shoot him in the back.
Elected to the Dáil in the newly independent Ireland, Briscoe works with Patrick Little to bring through a law limiting the interest that can be charged by moneylenders and also, as he writes, “made it illegal for a married woman to borrow money without the knowledge and consent of her husband, for these foolish ones are always the easiest prey of the moneylenders.”
During World War II, Briscoe, at this time a member of Dáil Éireann, comes under close scrutiny from the Irish security services. His support for Zionism and his lobbying on behalf of refugees is considered potentially damaging to the interests of the state by officials from the Department of Justice. He is an admirer and friend of Ze’ev Jabotinsky and his campaign to liberate the Jews. Between 1939 and 1940, he along with John Henry Patterson, a former commander of both the Zion Mule Corps and later the 38th Battalion of the Royal Fusiliers, are involved in fund raising for the Irgun in the United States. Jabotinsky while head of Irgun visits Dublin to receive training in guerrilla warfare tactics against the British under the instruction of Briscoe. During the period Briscoe describes himself as the “Chair of Subversive Activity against England.” He wishes for Ireland to give asylum to Jews fleeing Nazi Germany, but does so discreetly in order not to be accused of compromising the neutrality policy of the Fianna Fáil government.
After World War II Briscoe acts as a special advisor to Menachem Begin in the transformation of Irgun from a paramilitary group to a parliamentary political movement in the form of Herut in the new Israeli state. The party later becomes Likud. As he had already been a key figure in the formation in his own Fianna Fáil party out of the Anti-treaty IRA post Irish independence but not before a bitter Civil War, he prompts Begin to make the transition immediately after the Altalena Affair in order to avoid a similar civil conflict.
Briscoe serves in Dáil Éireann for 38 years and is elected 12 times in the Dublin South and from 1948, Dublin South-West constituencies. He retires at the 1965 Irish general election, being succeeded by his son, Ben, who serves for a further 37 years. In 1956, he becomes the first Jewish Lord Mayor of Dublin, although he is not the first Jewish Mayor in Ireland. That title belongs to William Annyas, who was elected Mayor of Youghal, County Cork in 1555. He serves a one-year term and is re-elected in 1961. His son Ben is also a Fianna Fáil TD, and he too serves as Lord Mayor of Dublin from 1988–1989.
Briscoe’s memoir, For the Life of Me, is published in 1958.