Museums Connect stands at the intersection of public history and public diplomacy. The program, which has both public history and public diplomacy agendas, is sponsored by the United States Department of State and administered by the American Alliance of Museums. This dissertation examines the competing impulses of transnational public history and public diplomacy made manifest in Museums Connect and its ramifications for public history theory and practice. The project demonstrates both the seeming similarities between public history’s ideas of shared authority, dialogic museum practice, and community engagement and public diplomacy’s “people-to-people” diplomacy, as well as the limits of these similarities. This dissertation also considers the ramifications of these dynamics on museum and public history practice and theory. It is shown that the assumptions of public diplomacy found in Museums Connect inform the program’s structure and operation, while also precluding a truly shared authority between the American museums and their international partners. The appointment of the American museums as “lead” museums and the Department of State’s choice to focus on young people as the target audience for the program foregrounds didactic relationships between the museums and their “communities” for the projects. Through three case studies of Museums Connect projects between the United States and Afghanistan, Morocco, and South Africa, this dissertation challenges the seminal theoretical literature of public history, articulated in Michael Frisch’s A Shared Authority, that interpretive and meaning-making authority in public history is inherently shared. Each case study reveals different factors that either promote or preclude more balanced power dynamics between the museums and their communities within the broader power dynamics established by the grant. Staff reflection-in-action, project activity and partner museum choice, and the non-American public history and museological contexts are all revealed to uniquely influence the dynamics between the museums and their communities. Throughout, the agency of the non-American participants, highlighted through the responses and reactions to the unequal dynamics of the projects, complicates notions of the singular democratic public sphere that underpin the paradigm of the museum as forum.