The United States and South Africa, exemplars of "archsegregation," have been constituted within an arc of historical racialized delineations which began with the centering, and subsequent overrepresentation, of European maleness and whiteness as the sole definition of Man. Globally present and persistent, these racialized delineations have been localized and spatially embedded through the tools of urban planning. This arc of racialized otherness, ineffectively erased, continues to inform the racially differentiated geospatial, health, social, and economic outcomes in contemporary urban form and functions for Black communities. It is within this historical arc, and against these differentiated outcomes, that contemporary urban discourse and contestation between individuals and institutions are situated. This historical othering provides not just a racialized geo-historical contextualization, but also works to preclude the recognition of the some of the most vulnerable urban community members. As urbanists and advocates strive to co-create urban space and place with municipalities, meeting the needs of these residents is imperative. In order to meet these needs, their lived experiences, and voices must be fully recognized and engaged in the processes and programs of urban co-creation, including in digital spaces and forums. Critical to achieving recognition acknowledging and situating contemporary digital discourses between local municipalities, Black residents, and Black networks within this historically racialized arc is necessary. In doing so, explore if, and how, race, specifically Blackness, is enacted in municipal digital discourse, whether these enactments serve to advance or impede resident recognition and participation, and how Black users, as residents and social network curators, engage and respond to these municipal discursive enactments. This exploratory research is a geographically and digitally multi-sited incorporated comparison of Chicago, Illinois, and Johannesburg South Africa. Using Twitter and ethnographic data collected between December 1, 2019, and March 31, 2020, this research layers digital ethnographic mixed methods and qualitive mixed methods, including traditional ethnographic, digital ethnographic, grounded theory, social change and discourse analysis, and frame analysis to explore three research goals. First, explore the digital discursive practices and frames employed by municipalities to inform, communicate with, and engage Black communities, and, if and how, these frames are situated within a historically racialized arc. Second, identify the ways in which Black residents, in dual discursive engagements with local municipalities and their own social networks, interact and engage with the municipal frames centering on Blackness. Third, through ethnographic narratives, acknowledge the marginalized residents of the Central Business District of Johannesburg, South Africa as "agents of knowledge," with critical and valuable knowledge claims which arise from their lived experiences anchored within racialized place and space. In doing so, support the efforts of these residents in recentering the validity of their knowledge claims in the co-creation of urban place and space. Additionally, in situating the city within a historically racialized arc develop novel frameworks, the racialized palimpsest city and syndemic segregation, through which to explore contemporary urban interactions and engagements. / Doctor of Philosophy / The United States and South Africa, exemplars of "archsegregation," have been constituted within an arc of historical racialized delineations which began with the centering, and subsequent overrepresentation, of European maleness and whiteness as the sole definition of Man. Globally present and persistent, these racialized delineations have been localized and spatially embedded through the tools of urban planning. This arc of racialized otherness, ineffectively erased, continues to inform the racially differentiated geospatial, health, social, and economic outcomes in contemporary urban form and functions for Black communities. It is within this historical arc, and against these differentiated outcomes, that contemporary urban discourse and contestation between individuals and institutions are situated. This historical othering provides not just a racialized geo-historical contextualization, but also works to preclude the recognition of the some of the most vulnerable urban community members. As urbanists and advocates strive to co-create urban space and place with municipalities, meeting the needs of these residents is imperative. In order to meet these needs, their lived experiences, and voices must be fully recognized and engaged in the processes and programs of urban co-creation, including in digital spaces and forums. Critical to achieving recognition acknowledging and situating contemporary digital discourses between local municipalities, Black residents, and Black networks within this historically racialized arc is necessary. In doing so, explore if, and how, race, specifically Blackness, is enacted in municipal digital discourse, whether these enactments serve to advance or impede resident recognition and participation, and how Black users, as residents and social network curators, engage and respond to these municipal discursive enactments. This exploratory research is a geographically and digitally multi-sited incorporated comparison of Chicago, Illinois, and Johannesburg South Africa. Using Twitter and ethnographic data collected between December 1, 2019, and March 31, 2020, this research layers digital ethnographic mixed methods and qualitive mixed methods, including traditional ethnographic, digital ethnographic, grounded theory, social change and discourse analysis, and frame analysis to explore three research goals. First, explore the digital discursive practices and frames employed by municipalities to inform, communicate with, and engage Black communities, and, if and how, these frames are situated within a historically racialized arc. Second, identify the ways in which Black residents, in dual discursive engagements with local municipalities and their own social networks, interact and engage with the municipal frames centering on Blackness. Third, through ethnographic narratives, acknowledge the marginalized residents of the Central Business District of Johannesburg, South Africa as "agents of knowledge," with critical and valuable knowledge claims which arise from their lived experiences anchored within racialized place and space. In doing so, support the efforts of these residents in recentering the validity of their knowledge claims in the co-creation of urban place and space. Additionally, in situating the city within a historically racialized arc develop novel frameworks, the racialized palimpsest city and syndemic segregation, through which to explore contemporary urban interactions and engagements.