O'Connell is one of the most famous names in Irish history. The O'Connells can trace their ancestry back to Eremonium Aengus Tuirneach, who was High King of Ireland in about 280 B.C. There were three distinct septs, in Co. Derry, in Co. Galway and, most importantly, in Co. Kerry, where it is one of the leading septs.

In Co. Kerry, the name is still prevalent. The Kerry O'Connells always had a broad European outlook, and this was evident in the most famous O'Connell, Daniel O'Connell, known as the Liberator, who was born near Cahirciveen in 1775 and died in Genoa in 1847. He conducted many crusades, most notably and successfully for Catholic Emancipation in Ireland in 1829.

The ruins of his birthplace can be seen just outside Cahirciveen, while his great house and estate at Caherdaniel in Co. Kerry are well preserved, with many mementoes in the house. The estate and house can be freely visited. The O'Connell Monument in O'Connell Street, Dublin, are both named in his honour.