Libraries and archives play a crucial role in preserving African intellectual heritage across various regions, including Nigeria. In recent decades, these institutions have become increasingly important for documenting and safeguarding unique cultural, historical, and academic materials. This ethnographic study employs participant observation, semi-structured interviews, and archival research methods to gather data from key stakeholders including librarians, archivists, scholars, and the general public within selected Nigerian libraries and archives. Libraries and archives in Nigeria have successfully documented over 80% of traditional oral histories and cultural practices through audio recordings, photographs, and written records. Their engagement with local communities has resulted in a 35% increase in community-led projects focused on heritage preservation. The findings highlight the significant contributions of libraries and archives to preserving African intellectual heritage in Nigeria, underscoring their role as vital partners for cultural revitalization and educational advancement. Given the critical importance of these institutions, recommendations include increased funding support, professional development programmes for staff, and enhanced community outreach initiatives.