Henri de Tonti (1649/50 - 1704) was an Italian-born soldier, explorer, and fur trader in the service of France.
Henri de Tonti, a Sicilian, was mostly likely born near Gaeta, Italy in either 1649 or 1650. He was the son of Lorenzo de Tonti, a financier and former governor of Gaeta. Alphonse de Tonti, one of the founders of what is now Detroit, was his younger brother.
His father, Lorenzo, was involved in a revolt against the Spanish viceroy in Naples, Italy and was forced to seek political asylum in France around the time of Henri's birth.
In 1668, Henri joined the French Army and later served in the French Navy. During the Third Anglo-Dutch War, Henri fought the Spanish at the battle of the Messina Revolt, lost his right hand in a grenade explosion and, from that time on, wore a prosthetic hook covered by a glove, thus earning the nickname "Iron Hand".
In the summer of 1678, Tonti journeyed with the famous René-Robert Cavelier, Sieur de La Salle, who recognized him as an able associate. La Salle left Tonti to hold Fort Crèvecoeur in Illinois, while La Salle returned to Ontario.
In the spring of 1682, Tonti journeyed with La Salle on his famous descent of the Mississippi River.