A google.com search using the query, What are the origins of the
Fir Bolg?, turned up 815 links. (including the one mentioned
below.) thefreedictionary.com is where I found the following as
well as other related info. In Celtic mythology, the Firbolgs ("men
of the bags") were early gods of Ireland that attacked the
Fomorians. They fought to a standstill and both sides lived in
Ireland until the Firbolgs were exterminated by the Tuatha de
Danaan ("people/children of Danu"). Also spelled Fir Bholg Hi,this
bulgarian wants to contribute a little info concerning the ancient
Fir Bolgs. Yes, there are proto bulgars from Eastern Europe.
Actually to be precise from ancient Sumer since they were
cimmerians. After the fall of ancient Sumer a number of them along
with slavs,celts and others will go to Babylon. With the fall of
the latter they moved on to Egypt where around or after the
invasion of the Sea Peoples,Egypt's pharaoh expelled them from his
kingdom. The proto-bulgars went to the Balkans and some of them
sailed to Ireland afterwards. Those bulgars that went to Eire or
part of the bulgar nation was known as Fir Bolgs for the leather
bags and belts all bulgars were known to wear. Danubian Bulgaria
founded in 681 A.D had kings from the first bulgarian dynasy with
the same names as Fir Bolg kings and their offspring. Danubian
Bulgaria had kings with names like...Umor,Symeon - 8th and 10th
century A.D. Our present prime minister and also the former child
king has the name Simeon. Also female Fir Bolg names like Etar are
archaic bulgar names.The Fir Bolg name Beoan is widely used archaic
and present day bulgarian name Baian or Boyan.Batbeoan is also
bulgar name. The Fir Bolg name Adar is purely old bulgar name. When
the Tuatha De Danann/ancient goths from nowdays Denmark/ conquered
the Fir Bolgs they put and end to finno-ugrian domination of
Ireland. Yes the bulgars of present day Bulgaria were melted in the
slavic and gotho-thracian pot but many old bulgar words,their
ancient calendar,numbers and else remains part of modern bulgarian
language and customs.