This document describes the construction of a historical climate dataset for the IGB river basins, which has been constructed for widespread use in the HI-AWARE project. The dataset covers the period from 1 January 1981 to 31 December 2010 with a daily time step and covers the IGB river basins at 10x10 km spatial resolution. Additionally, the upstream parts of the basins are covered at 5x5 km spatial resolution in a separate dataset to account for the larger variability in mountainous terrain. The methods used to generate the dataset have been discussed and the contents of the dataset have been illustrated in this document.