Previous research in the field of heritage language (HL) acquisition has focused on the connection between frequency of language use and HL speakers' connection to and maintenance of their HL. This dissertation introduces the concept of positioning through discourse into the study of HLs to show evidence that while frequency of HL use contributes to working HL abilities, the way that HL speakers are positioned contributes to how strongly they identify with their HL. Additionally, the way that the HL speakers in this study are positioned by their teachers, parents, siblings, peers, and school administrators has led them to create a new community of practice in which the identity feature of being HL speakers of Russian is the basis for membership. The data for this dissertation come from an ethnography at a primary school in rural Oregon, working with generation 1.5 and generation 2 HL speakers of Russian and/or Ukrainian. Multiple case studies were conducted, focusing primarily on three students from Ukraine and Latvia: fifth grader Darya, fourth grader Elena, and first grader Alla at home and at school as they were socialized (and socialized others) into situational language choice and use for interactional purposes. 54 hours of in-class and playground video and audio recordings along with 21 hours of in-home audio recordings provide the primary data for these focused case studies, accompanied by interviews with the HL students, their teachers, and their parents. Through in-depth discourse analyses of the transcribed data and a quantitative analysis of the frequency of in-home language use, the findings show that the students' multilingual selves are a combination of their actual language abilities reflective of their in-home language use patterns and their self-claimed multilingual identities reflective of how they are discursively positioned by others. Finally, the students' experiences of being positioned always by their teacher as HL "speakers" rather than just "learners" through phonological and discursive socialization in the HL classroom play an important part in their positive orientation to being HL speakers in their future goal narratives, which notably include the continued presence of their HLs as a central focus of their lives. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]