The Roger Williams Code

Roger Williams’ last known theological work lurking in the margins of an old book in an encrypted secret code—"An Essay Towards the Reconciling of Differences Among Christians." Courtesy John Carter Brown Library at Brown University.

How a team of scholars decrypted a secret language—and discovered the last known work of the American theologian.


For more than a century, a small, leather-bound book has sat collecting dust and attracting little attention in a gray stone library on the corner of Brown University’s Main Green in Providence, R.I. In a library full of old and obscure texts, the 234-page quarto was older and more obscure than most. Its brown, battered leather cover was blank, its title page missing, and its author unknown. Inside, a series of inscrutable symbols filled every inch of the book’s margins: Scrawled in black ink were what looked like a combination of Greek, Hebrew, and some wholly invented characters. Who wrote them? And what do they say?

The only hint came from an unsigned note attached to the book and dated Nov. 11, 1817. It read, in part, “The margin is filled with Short Hand Characters, Dates, Names of places &c. &c. by Roger Williams or it appears to be his hand Writing…. brot me from Widow Tweedy by Nicholas Brown Jr.”

Despite this intriguing reference to the man who founded Rhode Island and brought the idea of religious liberty to the New World, the book languished—until an offhand remark at a small lecture in 2010 led a team of Brown scholars and undergraduates to crack the code, confirm it was written in Roger Williams’ hand, and discover, this summer, his last known work of theology.



On a late fall day in 2010, Ted Widmer, then-director of Brown’s John Carter Brown Library, was giving a talk on Williams’ life and legacy to about 20 members of the Pembroke Club, a group of Brown alums. The attendees were “mostly people with either gray hair or no hair,” says Bill Twaddell, a retired diplomat and member of the library’s board of governors who sat in on the lecture.

At one point, Widmer (an occasionalcontributor to Slate) mentioned the book and the suspicion that Williams had authored the code in its margins. Twaddell’s ears perked up. Why not scan the code and let computers attempt to crack it?

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