At first I had some trouble finding information about Give-Away Day apart from this article. I did find general information about a Native American Give-Away tradition, including a blog post on the topic, and even a Christmas book called The Give-Away: A Christmas Story in the Native American Tradition. But as a July 4 tradition, I couldn’t find much. It sounded a little odd that Sioux and Dakota Indians just happened to celebrate the 4th of July. I suspected the article may have been mistaken.
Then I found a chapter from a textbook by the Montana Historical Society [pdf] which describes how agents of the Commissioner of Indian Affairs discouraged traditional ceremonies among the Native Americans. So instead, the Natives adopted their own versions of American holidays:
Even honest agents thought they were helping Indians by forcing them to abandon their traditional cultures and to adopt mainstream (majority) American culture. Agents pressured tribal members to change their social customs, dress in European-style clothing, live in rectangular houses, become Christian, send their children to school, and learn farming and ranching the Euro-American way.
Agents often outlawed Indian religious ceremonies like the Sun Dance. They discouraged give-away ceremonies, a traditional practice of honoring the Creator by giving away food, blankets, horses, and other forms of wealth. If people performed their traditional practices or religious rituals, they could lose their food rations or be arrested. They also were not allowed to leave their reservations without a pass…
Montana’s Indians knew they needed to learn new skills and find new ways to support themselves. But they refused to abandon their tribal identities and cultural traditions to survive.
They performed give-aways and held religious ceremonies in secret. They turned patriotic and religious holidays—like the Fourth of July and Easter—into celebrations of their own traditions.
In 1898 the tribes of the Flathead Reservation held their first Fourth of July pow-wow (an American Indian celebration). They staged parades, held contests, sang and drummed together, and danced traditional dances like the War Dance and the Snake Dance deep into the night. Indians on other reservations also held celebrations on July 4. The organizers assured the reservation agent that these gatherings were purely social, but they actually performed important religious and tribal ceremonies.
INDIANS HAVE A CELEBRATION OF THEIR OWN JULY 4: They Call It Give-Away Day Among the Dakotas and the Sioux Tribes, and They Give Presents to Those They Wish to Honor. (PDF)
From July 2, 1911