The rapid proliferation of the Internet of Things (IoT) across Kenya is reshaping key sectors, including agriculture, healthcare, energy, and urban planning, through data-driven innovations. However, the widespread reliance on foreign-manufactured IoT devices and cloud infrastructure raises pressing concerns about national data governance and sovereignty. This paper examines how the unregulated adoption of IoT technologies affects Kenya's control over its data and digital ecosystem. The study hypothesises that the dominance of off-the-shelf IoT devices, many of which regularly transmit user and infrastructure data to external servers, creates opaque transnational data flows that undermine national oversight and pose significant national security risks. To investigate this, the research employs a mixed-methods approach. First, the study engages in a policy analysis of Kenya's existing ICT laws, data protection regulations, and other relevant frameworks. Second, we undertake infrastructure mapping to identify how IoT deployments interface with foreign data infrastructures. Third, it carries out a systematic review of academic literature, government reports, and grey literature to contextualise the political and economic implications of foreign-dominated IoT ecosystems. The central question guiding the analysis is: How does the unregulated adoption of IoT technologies affect Kenya's control over its data and digital ecosystem? The findings reveal substantial legal, regulatory, and technical gaps in IoT regulation that permit unrestricted data extraction and external surveillance. Framing the analysis within theories of digital sovereignty and postcolonial technopolitics, the paper argues for urgent reforms in Kenya's digital governance strategies. The study proposes a roadmap that includes investing in domestic IoT innovation, strengthening governance mechanisms for cross-border data flows, and establishing enforceable data localisation standards. This paper offers actionable insights for Kenya and emerging economies aiming to reclaim agency over their digital futures.