The Northern Black Polished Ware culture (NBPW/NBP) of the South Asia (ca. 700 BC–200 BC) is an Iron Age culture, succeeding the Painted Grey Ware culture. It developed beginning around 700 BC, or in the late Vedic period, and peaks from circa 500 BC – 300 BC, coinciding with the rise of the Mauryan Empire.
Malik and other scholars have noted similarities between NPB and Harappan cultures, among them the ivory dice and combs and a similar system of weights. Other similarities include the utilization of mud, baked bricks and stone in architecture, the construction of large units of public architecture, the systematic development of hydraulic features and a similar craft industry. There are however also important differences between these two cultures, e.g. in the NBP culture rice, millet and sorghum become more important. The NBP culture may reflect the first state-level organization in South Asia.
Source : Wikipedia