Final answer:
The Civil Rights leader who resonated with those who found Martin Luther King Jr. too accommodating was Malcolm X, known for his advocacy for self-defense and more immediate action against racial injustice.
Step-by-step explanation:
The Civil Rights leader who gained popularity among blacks who felt that change was occurring too slowly and viewed Martin Luther King Jr. as too accommodating was Malcolm X. Malcolm X advocated for a more forthright approach to civil rights, arguing that African Americans should defend themselves against white aggression "by any means necessary" and was critical of King's strategy of nonviolent protest and incremental change. Unlike King, who had a southern base and a philosophy of integration and non-violence, Malcolm X had a northern, urban following and was associated with the Nation of Islam, which promoted Black self-sufficiency and separation from white society.
Many African Americans, particularly in northern urban areas, were drawn to Malcolm X's more militant message, which they felt more accurately reflected their experiences of systemic racism and offered a more tangible form of resistance. His views were seen by many as a call to action and self-empowerment, contrasting with what they perceived as the slower, legalistic approach favored by other civil rights leaders.