The son of a Lithuanian immigrant, and brought up in a strictly orthodox Jewish family, Robert Briscoe (1894-1969) was sent to America by his father in 1914, apparently for fear of conscription -- incidentally, the British never imposed conscription in Ireland because of overwhelming objection from the Irish population. Briscoe returned to Ireland after the Easter Rising in 1916. He joined Fianna Eireann and was sent by Michael Collins to Germany and United States to procure arms for the IRA.
Briscoe was a major political figure in Ireland and the first Jewish lord mayor of Dublin. He became Michael Collins's arms procurement officer in 1919, took the anti-treaty side in the Irish civil war, became a TD and lord mayor of Dublin on two occasions. Briscoe was also a Zionist, like Belfast-born Chaim Herzog, whose father, Yitzhak HaLevi Herzog, provided a safe house for republicans in Dublin.
Briscoe was a friend of Ze'ev Jabotinsky and went to New York in February 1939 to raise money for the Irgun Zvai Leumi, the military arm of Jabotinsky's Revisionist Zionist Movement. (A propos this, note the racist views of Wolfgang von Weisl, the financial director of the movement.) While in New York, Briscoe also had another mission - to get to President Roosevelt with a plan by Jabotinsky to evacuate a million Jews from eastern Europe to Palestine within two years.
On page 268 of his memoir, For the Life of Me, Briscoe tells us that, in 1938, the Revisionists sent him to make yet another proposition to Jozef Beck, the Polish minister of foreign affairs:
On behalf of the New Zionist Movement ... I suggest that you ask Britain to turn over the Mandate for Palestine to you and make it in effect a Polish colony. You could then move all your unwanted Polish Jews into Palestine. This would bring great relief to your country, and you would have a rich and growing colony to aid your economy.
See this Wikipedia (English) articleEvents involving Robert Briscoe: