Although often reputed to be the lesser half of a magnificent city, Northside Dublin's history is every bit as important as that of the districts south of the River Liffey and cannot be properly differentiated. From the first millennium A.D. when Vikings and Normans clashed for control of the island, through the Middle Ages, to the struggle for independence, the history of Dublin City's North is intertwined with that of Ireland.
The ruins of a 12th century Norman castle at Castleknock, thought to be built in turn on the ruins of a Viking fortification, provide evidence of the earliest recorded historical events on the isle. Castleknock is now home to a college of the same name.
The Middle Ages saw increasing numbers of English and Welsh settlers throughout the city, most notably in the rural north. This settlement would lay the foundation for future conflict as native Gaelic-speaking people were segregated to Irishtown south of the Liffey. The North Dublin populations of both Irish and English alike suffered tremendous losses during the Black Death of the mid-14th century.
At the north end of O'Connell Street lays Parnell Square, which remains an impressive and significant neighbourhood for its preserve of Georgian architecture. In the 1700s, when it was known as Rutland Square, it was considered to be the city's richest district. To this day the wealth of that period can be seen in the Rotunda Hospital, whose construction and gardens helped shape the surrounding square.