These dancers were from the Lake county band of Pomo, visiting to perform at the Sherwood Valley Rancheria ceremonial grounds.
Frybread is made from a wheat flour dough, and is a common staple found widely at American Indian events. It has a thick but puffy texture, and is fried in oil. If you can imagine something halfway between some Asian Indian flat breads, and a Mexican flour tortilla, this might be it. I first tried it at a roadside restaurant on a Navajo reservation in Arizona. The woman on the left, below, is holding some fried seaweed, gathered from the Pacific Ocean shore.
I didn't hear where this second group of Pomo dancers came from.