The civil rights pioneer known for their role in the Montgomery Bus Boycott is Rosa Parks. Her refusal to give up her bus seat to a white passenger on December 1, 1955, became a pivotal moment in the American civil rights movement. Parks was arrested, catalyzing a widespread boycott of the Montgomery bus system led by Martin Luther King Jr.. This action not only challenged systemic racism but also highlighted the power of peaceful protest. Parks' courageous stance demonstrated the impact of individual actions in the fight for justice and equality, inspiring future generations to engage in civil rights activism.