Alcatraz Island later invalidated the sale and paid Frémont nothing. Frémont and his heirs sued for compensation during protracted but unsuccessful legal battles that extended into the 1890s. Following the acquisition of California by the United States as a result of the Treaty of Guadalupe Hidalgo (1848) which ended the Mexican–American War, and the onset of the California Gold Rush the following year, the U.S. Army began studying the suitability of Alcatraz Island for the positioning of coastal batteries to protect the approaches to San Francisco Bay. In 1853, under the direction of Zealous B. Tower, the United States Army Corps of
Alcatraz Federal Penitentiary Prisons. The purpose of this transfer was to punish those involved in the rampant crime which prevailed in the country in the 1920s and 1930s. The United States Disciplinary Barracks on Alcatraz was acquired by the United States Department of Justice on October 12, 1933, and the island became a Federal Bureau of Prisons federal prison in August 1934. The $260,000 conversion to the federal prison took place from January 1934. George Hess of the United States Public Health Service was appointed the chief medical officer of the prison and Edward W. Twitchell became a consultant in psychiatry for Alcatraz