This dissertation study examined how teachers in four newcomer schools conceptualized and implemented social studies education for newcomer Latino/a youth. I designed this multi-site, collective case study to examine the perspectives and decision making of four social studies teachers' enacted pedagogy for Latino/a newcomer students. I documented how social studies teachers (U.S. History and Global History) were teaching Latino/a newcomer youth within urban newcomer high schools through the research question: how do four secondary teachers conceptualize and implement social studies education for newcomer Latino/a youth? As evidenced in their culturally and linguistically relevant pedagogy, teachers in this study provided constant support, encouragement, and opportunity for Latino/a newcomer students to succeed academically, and encouraged active civic engagement by using students' cultural, linguistic, and civic knowledge and experiences as central to their pedagogy. I analyzed the findings within and across four case studies to develop an emerging grounded theory of culturally and linguistically relevant citizenship education. This developing grounded theory analyzed the intersections of culturally relevant pedagogy, linguistically responsive teaching, and active and engaged citizenship. These intersections and cross-case analysis of the four teachers' social studies pedagogy for newcomer Latino/a students developed five principles of culturally and linguistically relevant citizenship education. These principles included: pedagogy of community, pedagogy of success, pedagogy of making cross-cultural connections, pedagogy of building a language of social studies, and pedagogy of community-based, participatory citizenship. This study has the potential to add to and expand on the discourse regarding social studies pedagogy for culturally and linguistically diverse students (Ladson-Billings, 1995b; Lucas and Villegas, 2011), newcomer schools (Short and Boyson, 2000), English Language Learners (Cruz and Thornton, 2009), and citizenship education for newcomer youth (Salinas, 2006). Possibilities for future research might include examining how Latino/a immigrant students' cultural and linguistic experiences influence their perceptions of social studies and how they conceptualize citizenship. Furthermore, additional research might also explore how the findings in this study may be used to develop a more culturally and linguistically responsive teacher education program, create professional development opportunities for in-service teachers, and examine how elementary teachers and teachers in rural/suburban contexts conceptualize their social studies pedagogy for immigrant youth.