The Irish surname Fitzsimmons  is an Anglo-Norman French patronymic  from the personal name Simon. The name is also found in the Gaelicized form Mac Síomóin. The earliest settlers of the name in Ireland accompanied John De Courcy to County Down in 1177. Others of the same name followed the Prendergasts to County Mayo early in the next century. The most important line of this family came from Simonshide, a townland in Hertfordshire England, and settled in Dublin, Ireland in 1323. 

FITZSIMMONS RAISED FAMILY CREST RING