Costello
An Irish surname tied to the barony of Costello in County Mayo, with roots in an Anglo-Norman family name that was reshaped in Ireland.
The #1,093 most common surname in the United States (2010 Census) — about 1 in every 9,635 Americans shares it.
Etymology
The surname is commonly explained as a locational name from the barony of Costello in County Mayo, Ireland. One traditional derivation says it ultimately comes from the Anglo-Norman personal name Hostilio de Angulo, whose descendants were called Mac-Ostello, meaning 'son of Hostilio,' and that this form later developed into Costello. In other words, the name combines a family line with an Irish place-based identity, and the modern spelling reflects later anglicized changes.
History
Historical surname books connect Costello especially with County Mayo and the old barony of Costello. The name spread beyond Ireland as people from that area emigrated, and it appears in later English-language records and biographical notices. Because of its Irish setting, it is often treated as an Irish surname even though its deeper roots are Anglo-Norman.
Origin
Regions
Variant spellings
Fun fact
The name has a rare double backstory: a Norman personal name seems to have been reshaped into an Irish territorial surname tied to a whole barony.
From the historical record
“the 0. Germ, name Custica. Ferguson. COSTELLO. Among the many A- Norm. settlers in Ireland, temp. Henry II., was Hostilio de Angulo. His descendants were called Mac-Ostello (son of Hostilio) which by still further corruption became Costello. COSTER. COSTAR. Du. ''Rosier, deurwaarder van een Catholyke kerk," Marin's…”
— Patronymica Britannica: a dictionary of the family names of the United KingdomNotable people named Costello
- Elvis Costello (b. 1954)
Sourced from Wikidata; linked to their Wikipedia page.