Antonio Meucci

An Italian immigrant and good friend of Giuseppe Garibaldi (the unifier of modern-day Italia as we know it), Antonio lived on Staten Island and developed the first working model of what we now konw to be the analog telephone.  He used alternating current to transmit voice signals over copper wire years before Alexader Graham-Bell.  His life was anticlimactic, ending in poverty.  He was seriously injured in a steam boat explosion disabling him.  Due to large medical bills, his wife sold most of their possesions, including his working models and life's work.  His poor command of the English language (a disadvantage not shared by the Scottsman Graham-Bell) in addition to his hardship left him unable to extend his temporary patent (Caveat) or apply for a permanent one for his telephone model, which he dubbed the "teletrofono."   This allowed Graham- Bell to secure the patent and his role as the inventor of the telephone.  His work was recognized by Congress in 2002 as HRes. 269 which conclued his work made him the rightful inventor of the telephone.  https://en.wikipedia.org/wiki/United_States_HRes._269_on_Antonio_Meucci

His house remains preserved as a museum in Staten Island, NY. 

Guglielmo Marconi

Marconi was an Italian physicist and scientist who is widely credited for inventing  and developing long distance wireless signal transmission.  He shared the Nobel prize in Physics in 1909 with Ferdinand Braun for his contributions to long distance radio telegraphy.  He outlined his principles in Marconi's Law.  A true and important contributor to today's modern techology.

Scipione Riva-Rocci

Born in Italy in 1863, Riva-Rocci was a Pediatrician who invented a noninvasive method of measuring blood pressure using household material.  Dr Harvey Cushing, a renowned American neurosurgeon, later brought Riva-Rocci's work to the world's attention which ultimately lead to the development of the modern day sphygmomanometer.  In addition, Riva-Rocci also worked with Dr. Carlo Forlanini in developing iatrogenic pneumothorax in the treatment of pulmonary Tuberculosis prior the antiobiotic era.

Amerigo Vespucci

Born in Florence, Italy in 1451.  Amerigo was not born an explorer or sailor and acutally lead a privileged life early on.  His parents were wealthy and friends of the Medici family, that ruled Florence for centuries.  He eventually decided to pursue exploration after a failed business adventure in Spain.  He was a contemporary of Christopher Columbus and actually met him on one occasion. Under the Spanish flag, Amerigo embarked on 4 or 6 Voyages to the "New World" to explore what is modern-day South America.  It is for Amerigo Vespucci for which North and South America are named.

Enrico Fermi

Born in Rome, Italy in 1901, he is often referred to as the "architect of the nuclear age and atom bomb."  After immigrating to the USA, Dr Fermi, joined Columbia University and, later, the University of Chicago where succeeded in engineering the first fission reaction and, in the process, created new elements that did not exist on the standard element chart of the time.  This top secret experiment at the University of Chicago was the first successful nuclear "chain reaction" in fission and led the US government to receive the message in code saying "The Italian navigator has landed in the new world." As a member of the Manhattan Project, his orchestrated fission reaction was the basis of the development of the atom bomb that ultimately won World War II. Ironically, he was vehemently against the use of his science and discovery for the use of destruction.  His contribution to nuclear physics earned him a Nobel Prize and a place in history as one of the greatest nuclear physicists of all time. 

Filippo Mazzei

December 25, 1730 – March 19, 1816) was an Italian physician. A close friend of Thomas Jefferson, Mazzei acted as an agent to purchase arms for Virginia during the American Revolutionary War, after meeting and befriending Thomas Jefferson and Benjamin Franklin in London.

The great doctrine 'All men are created equal' and incorporated into the Declaration of Independence by Thomas Jefferson, was paraphrased from the writing of Philip Mazzei, an Italian-born patriot and pamphleteer, who was a close friend of Jefferson. A few alleged scholars try to discredit Mazzei as the creator of this statement and idea, saying that "there is no mention of it anywhere until after the Declaration was published". This phrase appears in Italian in Mazzei's own hand, written in Italian, several years prior to the writing of the Declaration of Independence. Mazzei and Jefferson often exchanged ideas about true liberty and freedom