During the late 10th and early 11th centuries, the rise of Brian Bóruma saw Waterford and a number of other Viking ports being brought firmly under the control of the O'Brien dynasty.
Control of these Viking ports was significant for would-be Irish High Kings as it granted greater access to international trade and manpower.
In 1170 MacMorrough allied himself with Richard de Clare, 2nd Earl of Pembroke (Strongbow); together they besieged and took Waterford after a desperate defence.
Waterford was occupied by Mountjoy in 1603 during the Nine Years War (Ireland) a rebellion led by Hugh O'Neill, ostensibly in the cause of Irish independence and the Catholic religion.
The motivation for Waterford's defiance lay in the people's demand for freedom of religion – they were led by Catholic priests and re-consecrated several churches in the city – although there were also mutterings about the nationality of the new king.
In 1783, George and William Penrose founded a glass factory, which would become Waterford Crystal, the most famous business in the city.
In the early 20th century John Redmond was MP for Waterford and leader of the Irish Parliamentary Party, which almost achieved home rule and a new parliament for Ireland.
These men opposed the Anglo-Irish Treaty of 1922 and therefore took the Republican side when the Irish Civil War commenced with the firing upon the Four Courts in late June 1922.
Arrested by his former comrades for supporting the Free State, he escaped disguised as a nun, to join the government forces in Kilkenny.
Prout placed his artillery on Mount Misery overlooking their positions and bombarded the Republicans until they were forced to evacuate the barracks and prison.