REGAN. BRIAN Lyrics Follow

The family name Regan, and its cognates O'Regan, O Regan, Reagan, O'Reagan, is an Anglicized form of the Irish surname Ó Riagáin or Ó Ríogáin, from Ua Riagáin. The meaning is likely to originate in ancient gaelic from ri "sovereign, king" and the diminutive -in, "the king's child", transliterating as "little king". Descendant of Riagán'; the name of two distinct families: one seated in ancient Meath, and the other in Thomond. The O'Regans of Meath were a branch of the southern Ui Neill and one of the four Tribes of Tara. Before the Anglo-Norman invasion, they were lords of south Breagh in Meath and the north of the present Co. Dublin, and appparently a powerful family. They took a leading part in the wars against the Danes. The annalists, under the year 1029, record a notable triumph of Mathghamhain Ó Riagáin, king of Breagh, over the foreigners, when he made prisoner Amhlaoibh, son of Sitric, king of Dublin, and only released him on payment of an enormous ransom, including the celebrated Sword of Carlus. The O'Regans were dispossessed soon after the Anglo-Norman invasion and dispersed through Ireland. The O'Regans of Thomond are a dalcassian family said to be descended from Riagán, son of Donncuan, the brother of Brian Boru. The O'Regans are now numerous all over Ireland. The name is often pronounced Ó Réagáin. The feminine unisex forename, Regan, is likely to have derived sometime later from the English royal name Regina.

Source: Wikipedia