Rosa Parks is often referred to as the "Mother of the Civil Rights Movement" due to her action of:

Rosa Parks is often referred to as the "Mother of the Civil Rights Movement" primarily because of her courageous act of refusing to give up her bus seat to a white man on December 1, 1955, in Montgomery, Alabama. This act of defiance against racial segregation became a pivotal moment in the Civil Rights Movement, symbolizing the struggle against injustice and inspiring others to take a stand for their civil rights. Parks’ actions led to the Montgomery Bus Boycott, which mobilized the African American community and drew national attention to the fight against racial discrimination. Her bravery and decision to resist the segregation laws highlighted the systemic inequalities of the time and helped to galvanize public support for the Civil Rights Movement. This is why her act is so significant and remains a foundational moment in the history of U.S. civil rights.