The event often referred to as the genesis of the American Civil Rights Movement is the Montgomery Bus Boycott, which began in December 1955. Sparked by the arrest of Rosa Parks for refusing to give up her bus seat to a white passenger, this boycott mobilized the African American community in Montgomery, Alabama, in a protest against racial segregation on public buses. Led by Martin Luther King Jr. and supported by various organizations, the boycott lasted for over a year and ultimately led to a Supreme Court ruling that declared segregation on public transportation unconstitutional. This successful nonviolent protest laid the groundwork for future civil rights activism across the United States.