The land for Rienzi Playground was developed by the City of New York as a school and community play area. The portion to the northwest was acquired in three parcels between 1884 and 1914, and P.S. 21, the Philip H. Sheridan School, was erected during that time. Another small sliver of land was assigned to the Board of Education for a kindergarten playground. The large eastern portion of the park was acquired in 1941.