Final answer:
Presidents Lyndon B. Johnson and John F. Kennedy presided over periods with high amounts of race riots, particularly in the 1960s. Johnson's administration saw widespread urban riots and Kennedy's tenure involved federal intervention in racial unrest. Earlier and later periods of American history also witnessed significant racial violence, such as the East St. Louis riot of 1917 and the Los Angeles riots of 1992.
Step-by-step explanation:
The presidents who presided over the most race riots in the United States were Lyndon B. Johnson and John F. Kennedy. During Johnson's administration, the nation witnessed profound urban upheaval, particularly between 1964 and 1968, a period marked by 329 riots in 257 cities. President John F. Kennedy's tenure also experienced significant racial turmoil, including the use of federal troops to quell rioting on college campuses. The cumulative effect of these riots during the 1960s reflected deep societal divisions and unmet needs in African American communities, despite the promises of the Great Society programs. The unrest underscored the inability of the government and civil rights groups to substantially address the economic and social disparities faced by African Americans at the time. Race riots also exploded in history prior to the 1960s, particularly in the South after the Civil War with significant losses both during and after Reconstruction. Moreover, the riots that ensued after the assassination of Dr. Martin Luther King Jr. are some of the worst the country had ever seen, affecting at least 125 cities. It's important to highlight that the legacy of the Civil Rights Movement was not just limited to legislation but also involved the social and economic strides that were yet to materialize for many African Americans during these presidencies. Another significant period of racial violence occurred during the early 20th century, notably the East St. Louis riot of 1917, which was one of the deadliest of its time, and the violence that marred the years after, including the incident in 1919. These events signaled deep racial tensions that the Progressive Movement failed to address. The latter part of the 20th century witnessed continued racial strife, epitomized by the Los Angeles riots following the Rodney King incident in 1992, highlighting ongoing disparities and perceptions of injustice within American society.