MARTINELLI is  a surname of Roman origins which has been derived from the Latin name Martinus [derivative of Mars - Roman God of War and Fertility].  It is a  patronymic surname meaning "son of Martin". The surname and it's variations can be traced back to several countries in Europe for hundreds of centuries. 

Variations and Diminutives

Czech:  Martinovsky 
English: Martin
French:  Martineau
Italian: Martinelli, Martinolli, Martini, Martino, DiMartini, and DiMartino. 
Polish:  Marcinkowski, Marciszewski
Portuguese:  Martins
Romanian:  Martinescu.
Spanish:  Martínez, San Martin, Martín
Sweedish:  Martenssen