WI: deValera executed?

What would have happened if Eamon de Valera had been executed after the 1916 Easter Rising? How would this affect the Irish War of Independence, and Irish politics afterwards? Would the Irish Civil War still have happened?
 
Who becomes the President of the Dail instead of de Valera? Is it Arthur Griffith? If so, the combination of Griffith and Collins probably prevents any split after the Treaty vote. There'd not be an obvious leader to organize a mass revolt against the Free State (even though there'd be plenty of people who'd want to do so) since nobody could clam the former prestige that de Valera had IOTL.
 
Top