The City of Pomona was named as a result of an 1875 naming contest held by the Los Angeles Immigration and Land Cooperative Association, real estate investors who sought to promote and resell the land. Citrus worker Solomon Gates won the competition with Pomona, the Roman goddess of fruits
On the 6th of January 1888, the name Pomona was formally adopted with the city’s official incorporation. Though the citrus industry didn’t come into force until later years, the representation granted by the goddess “Pomona” was astoundingly fitting and became associated with the citrus industry.
By 1911, Pomona was added as an extension to Los Angeles' Pacific Electric street railcar network. The "Big Red Cars" served much of the San Gabriel Valley into the Western Pomona Valley from 1911 through the 1950s.
At the same time, Pomona was beginning to acquaint itself with the automobile through a tourist service that ran from Pasadena’s Green Hotel to Pomona’s Palomares Hotel. By 1912, Pomona had a network of paved roads connecting it to neighboring cities.
World War II marked a turning point for the city of Pomona as California was transformed into a hub for the Pacific Theater. In the domestic sphere, the Pomona Fairgrounds were used for training and housing military personnel, held 5,400 Japanese-Americans awaiting internment, and detained German and Italian Prisoners of War. The war saw the rise of aircraft and shipbuilding companies, Lockheed, Douglas, Northrop, Kaiser, and North American to aid in wartime production.
Although the citrus industry thrived as its products supplied allied forces during World War II, the war's end signaled the industry's decline with it. Many groves were eventually sold to make way for land development and the city’s growing population. 
The 1980s saw the loss of companies like Broadway Glass and Pomona Tile, with a later loss of jobs in the closing down of defense contractor General Dynamics. As these industries departed, so did Pomona residents who no longer had a place of employment. The city’s demographics shifted as a result, going from a population that was mostly Caucasian to one is predominantly Hispanic. These minority groups grew into important parts of city politics, and now dominate the City's political sphere.
Pomona remains home to the Los Angeles County Fairgrounds (Fairplex), Autoclub Raceway in Pomona (Pomona Raceway), Fox Theater Pomona, Glass House Pomona, as well as a number of local and art history museums. Pomona, California - Wikipedia