The Santa Anita Assembly Center site is California Historical Landmark #934. In 1942 during World War II, the racetrack grounds were used as a processing and holding site for Japanese Americans who had been removed from their homes and communities for forced relocation and internment under President Franklin Roosevelt's Executive Order 9066. The Civilian Assembly Center at the racetrack became the largest and longest operating one of the eighteen, holding citizens until the Relocation Center camps were completed in interior areas of California and other states. More than 18,000 persons resided at the racetrack in primitive conditions.Arcadia City Library: "Santa Anita PACEMAKER" ; Homepage for 32 digitalized editions of the Santa Anita Assembly Center newspaper. (accessed 7.11.2014). Four hundred temporary tarpaper barracks were constructed on the racetrack grounds to house many of the detainees, where they lived three families per unit. 8,500 detainees lived in converted horse stalls. Bachelors were housed in the grandstand building. They had group showers, non-private bathrooms, and 24-hour armed surveillance. Each resident was given an "Army manufacture bed, one blanket and one straw tick."McAdam, Pat and Snider, Sandy. Arcadia: Where Ranch and City Meet, p. 147 The Assembly Center held people from late March through the end of October 1942, when the internees were relocated inland to permanent internment camps at Manzanar and Tule Lake in California, and eight others in Western states and Arkansas.
