No one person can take credit for the invention of American Sign Language. Its history reaches back to the early 19th century, when forms of sign developed among Deaf communities in New England. Early attempts at a signed form of English that replicated phonetic sounds gave way to a pure sign language with no reference to speech, combining forms of sign used by Deaf communities in New England with LSF (Langue des Signes Française), a French system invented in 1760. By 1835, ASL had become the standard language of Deaf instruction. 20 years later over 40% of teachers were also themselves deaf users of ASL.

The “origins of the American Deaf-World” — as Harlan Lane, Richard Pillard, and Mary French write in an article for Sign Language Studies – has “major roots in a triangle of New England Deaf communities.” Here, the first school for the Deaf that used ASL was founded by Thomas Gallaudet and Laurent Clerc; annual conventions brought together Deaf students and educators from all around the country; periodicals were founded; and, at one time, a Deaf commonwealth was proposed and “debated at length at the 1858 meeting of the New England Gallaudet Association.”

However, as the Vox video explainer points out, there’s another, far deeper history – notably the previous existence of Indigenous sign languages all over North America. One form of “Hand Talk” called Plains Indians Sign Language (PISL) represents “one of the oldest languages in North America.” It was not only a system of sign for the Deaf but also operated as a lingua franca among different language groups. PISL “was the means for commerce,” says PISL educator Lanny Real Bird. “It was the means for economics…. Plains Indian Sign Language was the medium for communication of intertribal nations.”

Melanie McKay-Cody, Professor at the University of Arizona and member of the Cherokee Nation West, shows how many of the gestures of Hand Talk more generally — or “North American Indian Sign Language” — can be found in ancient rock writing. Hand Talk has regional variations all over the continent, including a Northeast Indian Sign Language covering what is now New England, the upper Midwest, and the Mid-Atlantic. Researchers like McKay-Cody believe that this variant significantly influenced ASL through Native American children forced to attend the American School for the Deaf, which was then called the American Asylum for Dead Mutes.

The video presents compelling evidence for North American Indian Sign Language’s influence on ASL, and on American culture more generally, including a 1930 film of the Indian Sign Language Grand Council, “one of the largest gatherings of intertribal Indigenous leaders ever filmed.” Organized by General Hugh L. Scott, the purpose of the council was to preserve PISL. Concerned that “young men are not learning your sign language,” as he signed to the tribal leaders, Scott worried “it will disappear from this country.”

It so happened that ASL itself might have disappeared in the 1870s and 80s when fierce opponents of sign language — called “Oralists” and lead by Alexander Graham Bell — attempted to ban ASL and force Deaf students to communicate with speech and lip-reading. Graham’s mother was Deaf; his father invented a system of symbols called “Visible Speech” which Graham himself taught at a private school. Despite his efforts, ASL thrived.

As you’ll learn in the video, however, Scott and the tribal leaders he gathered had reason for concern all the way back in 1930. Few users of Indigenous sign languages remain after the generation of students forced to assimilate “were told,” McKay-Cody says, “that ASL was superior to whatever their Native sign was.”

Related Content:

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Evelyn Glennie (a Musician Who Happens to Be Deaf) Shows How We Can Listen to Music with Our Entire Bodies

Josh Jones is a writer and musician based in Durham, NC. Follow him at @jdmagness