Reanalysis data and simulations show, during the last millennium, that the evolution of precipitation in central Asia is out of phase (in phase) with that in the South Asian monsoon region and most of northern China (southern China) on a decadal scale. This linkage of precipitation changes in arid central Asia and humid monsoonal Asia is dominated by internal variability associated with the Interdecadal Pacific Oscillation and causes a similar linkage of moisture changes in the two regions.