As a result, early Americans “operated in multiple secret languages during the Revolution,” says Sara Georgini, the series editor of The Papers of John Adams, at the Massachusetts Historical Society. “They didn’t throw away those habits once the new nation got formed.” The Founding Fathers continued to rely on encryption throughout their careers: George Washington, Benjamin Franklin, Alexander Hamilton, John Adams, John Jay, and James Madison all made ample use of codes and ciphers to keep their communiqués from falling into the wrong hands.
But no one went as deep into the encryption game as Jefferson. Born in 1743 in Shadwell, Virginia, Jefferson was learning Latin, Greek, and French by the age of 9. He went to the College of William & Mary at 16, to study physics, math, and philosophy, and by early 1764, Jefferson, then 20 years old, was writing letters in code. At first glance, a cryptic letter he sent that year to John Page, a close college classmate, is difficult to parse: It drops Latin phrases in the middle of what sound like emotional ultimatums about an upcoming contractual agreement with some man, whose name is written in Greek characters.
“My fate depends on αδνιλεβ’s present resolutions: by them I must stand or fall,” Jefferson writes. But the Greek characters are in fact an anagram for Rebecca Burwell, a 17-year-old from Yorktown he wanted to marry. Four days later, Jefferson decided that his earlier code was too obvious. “We must fall on some scheme of communicating our thoughts to each other, which shall be totally unintelligible to every one but to ourselves,” he told Page.
Although most encrypted letters were a mixture of cipher and “plaintext,” deciphering them could be a patience-straining process. It was easy to mess up during the encoding or decoding process. Letters using dictionary and book codes—where the writer provided a set of numbers that indicated the page, column, and position where the word they wanted could be found in an agreed-upon book—could become garbled by line-counting errors.
The alternative was having secrets stolen and—then as now—even leaked in an embarrassing scandal. As some of the colonists grew more radical following the Boston Massacre, a cache of private letters by Massachusetts Governor Thomas Hutchinson and his lieutenant were leaked and published in newspapers up and down the Eastern Seaboard. In the letters, Hutchinson said that colonial Americans were owed only a fraction of the rights English citizens could expect. Americans took to the streets to burn effigies of the two men.
On Christmas Day in 1773 none other than Benjamin Franklin copped to being the source of the leak, a sort of colonial Julian Assange. He lost his job as deputy Postmaster General of North America, but things accelerated quickly toward revolution and war, raising the stakes for secret communications even higher. Soon, similarly compromising documents emerged from the offices of colonial governors in New York, Maryland, Virginia, and North Carolina—duly stolen and leaked to newspapers.