This dissertation seeks to trace a geneology of anti-Blackness within Mexican American and racial identity formation. By understanding the nuanced differences between white supremacy, racism against Mexicans and the structural racism of anti-Blackness, I believe that Mexican Americans and Black communities can build solidarity and successfully resist racism. I argue that global anti-Blackness and racial capitalism have been foundational in the development and sustainability of anti-Blackness within the Mexican American community. Furthermore, Mexican Americans, as a colonized people, have been subjected to discrimination, state sanctioned violence, harassment, and harmful national rhetoric. However, by creating and clinging to an ambiguous Mestizo Latinidad as a racial identity, Mexican American racial identity has been and continues to be anti-Black and harmful especially to Afro-Mexicans, Black Mexicans, and Indigenous Mexicans. Through archival research, large N survey data, and legal analysis, I argue that for Mexican Americans, racial identity has been and continues to be both an internal and an external negotiation; by which I mean Mexican Americans have negotiated for themselves their own racial identity (through legal processes, social Movements, and cultural reproduction). However, their racial identity has also been imposed by structures like white supremacy which names them a racialized other. Through these processes of negotiation, Mexican Americans have become complicit in reproducing and normalizing harmful anti-Black sentiments. Rather than joining Black communities in fighting oppression and white supremacy, history has demonstrated that Mexican Americans have often been complicit in the oppression of the Black community.