President Lyndon B. Johnson played a significant role in Black history during his presidency from 1963 to 1969. Johnson signed the Civil Rights Act of 1964 into law, which prohibited discrimination based on race, color, religion, sex, or national origin. This landmark legislation was a major victory for the Civil Rights Movement and helped to dismantle segregation and discrimination in various sectors of society.

Johnson also signed the Voting Rights Act of 1965, which aimed to overcome legal barriers at the state and local levels that prevented African Americans from exercising their right to vote as guaranteed by the 15th Amendment to the U.S. Constitution. The Voting Rights Act was a crucial piece of legislation in ensuring voting rights for all Americans, especially African Americans in the South.

Additionally, Johnson implemented various economic and social programs as part of his "War on Poverty," which aimed to address issues of inequality and poverty that disproportionately affected African Americans and other marginalized communities.

Overall, President Lyndon B. Johnson's actions and policies had a lasting impact on Black history and the ongoing struggle for civil rights and equality in America.