The Montgomery Bus Boycott began in 1955 when Rosa Parks was arrested for refusing to give up her seat to a white passenger, leading to a year-long boycott of the bus system organized by the Montgomery Improvement Association led by Martin Luther King Jr. in protest of racial segregation policies. The boycott faced opposition through legal and violent tactics by white citizens and officials aimed at undermining it. Ultimately, the boycott was successful as the US Supreme Court ruled that segregation on public buses was unconstitutional, overturning the segregation policies.