1823 – Born in Waterford, County Waterford, Ireland on the 3rd of August.
1801 – He joined the campaign for the Repeal of the Act of Union with Great Britain.
1845 – He became a founding member of the Young Ireland group.
1848 – Meagher and O’Brien went to France to study revolutionary events there, and returned to Ireland with the design for a new Flag of Ireland, a tricolour of orange, white and green gifted by the French.
1849 – Exiled to Tasmania for advocating insurrection in Ireland.
1852 – In January Meagher abruptly surrendered his "ticket-of-leave" and escaped to America.
– Meagher served the Union Army as a U.S. citizen.
1865-1866 – Acting governor of Montana Territory.
1867 – He traveled to Fort Benton, Montana, to receive a shipment of guns and ammunition sent by General Sherman for use by the Montana Militia.
– Died on the 1st of July.