The increased regulation of mobility that accompanied its late nineteenth-century expansion and acceleration is widely recognized. Regulatory practices reached out to distant shores and on board ships, heightening uncertainties and reshaping meanings of voyage and transit, especially for non-white passengers and crews. Travel and mobility are common themes in historical and other literatures. But less is known about experiences of uncertain or thwarted arrivals, involuntary departures, and indefinite transit resulting from practices governing steam-age mobility. People in transit illuminate the conditional openings and closures in such tropes as mobility, transit, and destination. Few spaces embodied and actualized 'transit' better than ships, and this article focuses on the role of ships as vessels of confinement. In equal parts about passengers and crews, it explores experiences of nominally free persons uncertainly afloat in a world marked otherwise by assured or accelerated oceanic mobility in three contexts that illustrate physical, political, and cultural constraints on maritime mobility in the age of steam. They are the 1914 voyage of the Komagata-maru, British merchant vessels employing Indian crews, and wartime subjection and resistance of Chinese crews on British and Dutch vessels.