Knowland became owner, editor, president and publisher of "The Oakland Tribune" on 3 November 1915. He wrote, "It is perfectly understood that what it "Tribune" does, rather than what it promises, will determine the true measure of its worth; and with this understanding, the "Tribune", under its new control, girds to its work." Many years and court battles with Hermina Peralta Dargie (widow of owner William E. Dargie) passed before Knowland had full control of the "Tribune". Knowland built the Tribune Tower, a city landmark at 13th and Franklin Streets. He had a great interest in restoring the California Missions. This had begun in 1903, with Mission San Antonio De Padua. He was a historical advisor during the 1927 California State Park Survey.