It was named after Anglo-American pioneer Jeremiah Morgan, a migrant from Alabama and Iowa who acquired 2,000 acres and developed a ranch here, starting in 1857.
The earliest historic occupants had long been small, highly localized tribes of Native Americans, who spoke dialects of the Bay Miwok language.
During the Spanish and Mexican periods, the Native Americans were displaced and colonial governments made large grants of land to high-ranking officials.
In addition, the adjacent Mount Diablo State Park, established in the 1920s, has been part of a trail network connected to the Morgan Territory Regional Preserve.
Its area ranges east from Riggs Canyon and Mount Diablo State Park to the Contra Costa Water District's Los Vaqueros watershed and EBRPD's Round Valley Regional Preserve.
[citation needed] Preserve trails are named for regional Native American peoples, such as the Volvon (one of five tribes in the Mt.
Diablo area who spoke dialects of the Bay Miwok language);[3] animals such as condor (molluk), prairie falcon, eagle and coyote; and for natural features related to the preserve's ranching history (Valley View, Blue Oak, and Highland Ridge).