Charles Trimble, a member of the Oglala Sioux Tribe who dedicated his life to advancing the causes of self-determination, sovereignty and human rights for Native Americans, died on March 2 at a hospital in Omaha. He was 84.

His daughter, Kaiti Fenz-Trimble, said he had been in failing health for some time.

Mr. Trimble, who overcame early poverty, wore many hats. He helped establish a news service for Native American newspapers. He mediated disputes between the tribes and the United States government. And he promoted economic development on tribal reservations.

He started, as well, Charles Trimble Company, a national consulting firm specializing in economic development on Indian reservations. He also founded Red Willow Institute, a nonprofit that provided technical and management assistance to Native American nonprofit organizations.

Mr. Trimble was concerned that issues of deep importance to Native Americans were going uncovered by the mainstream press. In 1969 he helped found the American Indian Press Association, a news service that covered Indian-related news in Washington and made the articles available to scores of tribal newspapers. More of an organizer than a working journalist, he brought together the tribal editors and helped them exchange ideas and decide which projects the Washington bureau should pursue. He was sometimes called “a founding father of Native American journalism.”