Finvarra

A family name originating in Westmarch denoting some members of Marquesa Dame Ailanthus Finvarra's Belted Family. Current bearers of the name are Ailanthus, Hannibal Finvarra, Blue Wolf Finvarra, and Ailil Fionnbharr.

History of the name (from Wikipedia)

King Finvarra, also called Finvara, Finn Bheara, Finbeara or Fionnbharr, is the High King of the Daoine Sidhe in Irish folklore. In some legends, he is also the King of the Dead. Finvarra is a benevolent figure who ensures good harvests, strong horses, and great riches to those who will assist him. Unfortunately, he is also a womanizer who frequently kidnaps human women.

He "lives" on Knockmaa, a hill in County Galway, north of Galway city. There is a ruin on the hill marked on Ordnance Survey maps as "Finvarra's castle". It is mentioned in manuscripts stretching back many centuries.

After the magical race the Milesians defeated the Tuatha de Danann, the Tuatha decided to leave. There was a group led by Finvarra who elected to remain in Ireland. They were the Daoine Sidhe. Finvarra negotiated a truce where they were allowed to remain in Ireland as long as they remained underground. There they lived among the trees underground and built great cities. A magical spirit race, who affected the affairs of men above ground, they eventually became known as the fairy folk. They were respected and feared, and no new structure was built without first asking the fairy folk for permission, or for their assistance and guidance. This gradually fell out of practice with the onslaught of modern civilization.