The park site was bought by the city in 1958, as part of the grounds for the Washington Junior High School, one block to the east. In 1966, it was chosen as the site for a park since the school had been rebuilt farther south on Jackson.
Financed by funds from Forward Thrust and Urban Renewal, the park was developed between 1972 and 1979. It was designed by the firm of Woo and Park.
In 1976, the Park Board began considering the name of Edwin T. Pratt for the park. The naming was to be contingent upon concurrence by the Seattle Urban League and then only if the development was to be part of a healthy, economic neighborhood improvement program.
In 1995, a water play area in the park, designed with an African theme for children, was dedicated in honor of Dr. Blanche Sellers Lavizzo, founding medical director of the Odessa Brown Children's Clinic.