Hale published a brief grammar and vocabulary in 1883 and confirmed the language as Siouan through comparisons with Dakota and Hidatsa. His excitement at finding an ancient Dakotan language that was once widespread in Virginia, to be preserved on an Iroquois reserve in Ontario, was considerable. Previously, the only recorded information on the language had been a short list of words and phrases collected by Lieutenant John Fontaine at Fort Christanna in 1716 and a few assorted terms recorded by colonial sources, such as John Lederer, Abraham Wood, Hugh Jones, and William Byrd II. Hale noted the testimony of colonial historian Robert Beverley, Jr.--that the presumably-related dialect of the Occaneechi was used as a lingua franca by all the tribes in the region of whatever linguistic stock, and it was known to the chiefs, "conjurers," and priests of all tribes, who even used it in their ceremonies, just as European priests used Latin. Hale's grammar also noted further comparisons to Latin and Ancient Greek in terms of the classical nature of Tutelo's rich variety of verb tenses available to the speaker, including what he remarked as an 'aorist' perfect verb tense, ending in "-wa".
James Dorsey, another Siouan linguist, collected extensive vocabulary and grammar samples around the same time as Hale, as did Hewitt a few years later. Frachtenberg and Sapir both visited in the first decade of the 1900s and found only a handful of words that were still remembered, by a very few Cayuga of Tutelo ancestry. Speck did much fieldwork in preserving their traditions in the 1930s but found little of the speech remaining. Mithun managed to collect a handful of terms still remembered in 1980.
The language as preserved by the efforts is now believed to have been mutually intelligible with, if not identical to, the speech of other Virginia Siouan groups in general, including the Monacan and Manahoac and Nahyssan confederacies as well as the subdivisions of Occaneechi, Saponi, etc.
In the 21st century, there has been interest, especially among descendants of the original native groups, in contemporary language revitalization.