-Lieutenant Thomas Leffingwell was born on 10 March 1624 at White Colne, Essex, England. He married Mary White born in Cranbrook, Kent, England, in about 1645. He migrated to Connecticut some time before 1637, maybe in the charge of an older sister. This was shortly after the settlement of Hartford, Connecticut in 1636. He married Mary White, daughter of Edward white and Martha King in about 1647. Thomas was a friend of the first Mohegan Chief Uncas. The following account is from Dr. Trumbull’s “History of Connecticut”:
 
“Uncas, with a small band of Mohegan Indians, was encamped on a point of land projecting into the river, and there closely besieged by their most inveterate foes, the Narragansetts. Finding himself in danger of being cut off by the enemy, he managed to send to his friends, the English Colony at Say-brook, the news of his extremity, with perhaps some appeal for help. "Upon this intelligence," says Trumbull, "one Thomas Leffingwell, an ensign at Saybrook, an enterprising, bold man, loaded a canoe with beef, corn and pease, and, under cover of the night paddled from Saybrook into the Thames, and had the address to get the whole into the fort. The enemy soon perceiving that Uncas was relieved, raised the siege. For this service Uncas gave said Leffingwell a deed of a great part, if not the whole of the town of Norwich. In June, 1659, Uncas, with his two sons, Owaneco and Attawanhood, by a more formal and authentic deed, made over unto said Lefingwell, John Mason, Esq., the Rev. James Fitch, and others, consisting of thirty-five proprietors, the whole township of Norwich, which is about nine miles square."
 
Thomas is said to be the inspiration for James Fenimore Cooper’s character “Hawkeye” in the “Last of the Mohicans”. It is interesting to note that Uncas wasn’t the “last of the Mohicans” but rather the first as he broke away from his mother Nation to establish the Mohicans. His friendship with Thomas and Uncas’s wisdom is evident in how Mohegans survived and thrived.