Established by an act of Congress passed on May 2, 1890, the Oklahoma Territory was formed from unassigned lands in the center of Indian Territory. 

Between 1890 and 1906, the area was enlarged by the addition of certain lands previously included in Indian Territory. Under terms of an enabling act approved June 16, 1906, Oklahoma and Indian Territories were joined to form the State of Oklahoma, which was admitted to the Union by presidential proclamation on November 16, 1907. 

Until the merger, the area known as the Oklahoma Territory was administered by several officials, including Territorial Governors appointed by the President. Between 1890 and 1907, the following persons served as Territorial Governors:

• George Washington Steele (1890-1891)
   
• Robert Martin (1891-1892)
   
• Abraham Jefferson Seay (1892-1893)
   
• William Cary Renfrow (1893-1897)
   
• Cassius McDonald Barnes (1897-1901)
   
• William Miller Jenkins (1901)
   
• William C. Grimes (1901)
   
• Thompson Benton Ferguson (1901-1906)
   
• Frank Frantz (1906-1907)

Papers and documents from the pre-statehood administrations of these territorial governors are available in the state's archives.

Annual Reports of the Territorial Governors
Papers of Oklahoma's Governors