In County Clare is located the barony of Bunratty where today can be found Bunratty Castle, built by the MacNamara Clan in 1425 A.D. According to the book, the "Families of County Clare" (Irish Genealogical Foundation, Michael C. O'Laughlin) - O'Hannons were found in both the Upper & Lower Bunratty barony, according to the 1659 Census. This is where our Érainn Dalcassian Hannan/Hannon ancestors lived for some two milleniums. Also found nearby are Ballyhannan North and Ballyhannan South townlands.

If one visits nearby Bunratty castle and has a discerning eye for what is around them...you will see stained glass in the castle windows bearing "3 cross pattees" on the ruler's coat-of-arms, which look very similar to the "3 cross pattees" on the O'Hannon coat-of-arms.

In the book, "Families of County Limerick" (IGF, O'Laughlin), we find that O'Hannons were also numerous in County Limerick. In fact, the late Edward MacLysaght (former Chief Herald and Genealogical Officer of the Irish Office of Arms) in his book "The Surnames Of Ireland" states that the O'Hannons were chiefly found in Co. Limerick. We would only add that Co. Limerick later became a prominent Hannan/Hannon location due to transplantation of our ancestors.

In the book, "Families of County Galway" (IGF, O'Laughlin), we find another branch of the Hannons (Ó hAnnáin) were numerous in southeast Galway as a sept affiliated with the Hy Many. These Ó hAnnáins were to be found in Counties Galway, Roscommon, Mayo and southern Sligo in Connacht. The author states these O'Hannons were "not too far from the Érainn Dalcassian sept of the same surname".