This paper presents the first millennial-scale reconstruction of Marine Isotope Stage (MIS) 11 (~400 ka) from the subarctic Pacific Ocean. We use diatoms, calcareous nannofossils, grain size, and carbon and nitrogen isotopes to examine changing productivity and sea ice. These change in sync with other regional and global records. Initially, MIS 11 is highly productive, due to increased upwelling. Sea ice declines gradually during this warm period, but is present throughout.