He lived in Dublin, where he was a Licensed Vintner, maintaining a long tradition by Tipperary men in the capital.
He was involved in the Easter Rising in Dublin in 1916. This led to him having legal difficulties over the licence of his public house. Shanahan consulted the lawyer and politician Timothy Healy who commented: -
He was elected for Dublin Harbour in the 1918 general election (defeating Alfred Byrne). Like other Sinn Féin MPs he did not take his seat at Westminster, but became a member of the revolutionary Dáil. He represented Dublin Harbour in the First Dáil 1919-1921.
Phil Shanahan's pub, in the notorious Monto district of Dublin (near the docks), was the scene of an execution ordered by Michael Collins (the Director of Intelligence for the Irish Republican Army as well as a Minister in the Dáil administration). A Dublin Castle spy, John 'Shankers' Ryan, was shot on 5 February 1921.
In 1921 a general election was held for the House of Commons of Southern Ireland. Republicans used this as an election for the Second Dáil. Shanahan was elected unopposed in the four member Dublin Mid West constituency. He was defeated in the election to the Third Dáil in 1922, as a member of the Anti-Treaty faction of Sinn Féin (which opposed the creation of the Irish Free State in the place of the Republic declared in 1919).
This is my great grandfather Philip Shanahan with the first dail members. Including Michael Collins and Eamon de Valera. He is in the top left of the picture. By Karl Dunne