The Tewa language is now considered to be of the Tanoan language family. Spoken in six pueblos in northern New Mexico and by many residents of Hano at Hopi First Mesa in Arizona, UNESCO has declared Tewa "definitely endangered" in Arizona and "severely endangered" in New Mexico due to the relatively few people who still speak it. In the interests of preserving the language, Esther Martinez published the San Juan Pueblo Tewa Dictionary in 1982. Her efforts to preserve the language gained national attention and in 2006, President George W. Bush signed into law the Esther Martinez Native American Languages Preservation Act. That legislation provided new funding for tribal programs to prevent further loss of heritage and culture.
A Tewa elder once told me that his people originated in the valleys west of Mesa Verde. We don't know what the relations were like but they picked up some of the Keresan technology and some of their religion back then. However, in the process of absorption, some things were changed: The iconography remained very similar but the meanings of certain terms used in their ceremonies seem to have been reversed.
Archaeologists say there may have been three main pushes of Tewa people into the upper Rio Grande area during the 1200s and 1300s. The first group likely traveled up the San Juan River, then crossed over the ridge and dropped to the south along the Ojo Caliente and Chama River drainages. An ancient pueblo, Tsama, has been found there along the Chama, tying the Tewa now downstream to residents of ancient Sand Canyon Pueblo, in the canyons to the west of Mesa Verde. They were possibly the famous Asa clan who migrated all over the countryside, gaining and losing people as they moved until they finally lost their language and heritage, merging at last into the Diné at Chinle.
The second major thrust went further east and to the north of Mesa Verde, until they crossed over the San Luis Valley and spent some time among the Plains tribes. There they learned how to hunt larger game and how to prepare and preserve their meat and fur. Then they crossed back through the mountains and descended south along the east bank of the Rio Grande into the Nambé River drainage. There, they settled in the upper mountains and only came down to the lower valleys to farm. Over time they began to feel safer, so they came down out of the mountains and began staying in the valleys year round. That's where they were when the Spanish arrived.
The third major push also came through the Ojo Caliente and Chama River drainages but they also spilled south into the northern Jemez Mountains and onto the Pajarito Plateau. From there they slowly pushed the local Keresan people to the south, into Frijoles Canyon. In the 1500s and 1600s, these groups moved eastward, down out of the mountains, and took up residence along the Rio Grande, where they are now.
There seems to have been a push for some to continue going south and they ventured into the Santa Fe and Galisteo Basins. In the Galisteo Basin, they displaced the Keresan people who later formed Santa Ana Pueblo. They didn't last long around Galisteo and by 1696, most of those Southern Tewa had left the area and moved to Hopi country, where most of their descendants remain.