how would you explain this category of americans?
They are an ethnic group of Americans with total or partial ancestry from any of the black racial groups of Africa
African Americans
African Americans (also referred to as Black Americans or Afro-Americans) are an ethnic group of Americans with total or partial ancestry from any of the black racial groups of Africa. 
which two key events in the civil rights movement took place in alabama Protests and boycott which campaign led to martin jr. getting arrested? The Birmingham campaign who were involved in starting this campaign? Martin Luther King Jr., James Bevel, Fred Shuttlesworth what was the aim of starting this campaign? To bring attention to the integration efforts of African Americans in Birmingham, Alabama.
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African Americans [SEP] Introduction
African Americans (also referred to as Black Americans or Afro-Americans) are an ethnic group of Americans with total or partial ancestry from any of the black racial groups of Africa. The term "African American" generally denotes descendants of enslaved black people who are from the United States, while some recent black immigrants or their children may also come to identify as African-American or may identify differently. African Americans constitute the third largest ethnic group and the second largest racial group in the US, after White Americans and Hispanic and Latino Americans. Most African Americans are descendants of enslaved peoples within the boundaries of the present United States.