The Northern Black Polished Ware culture ( NBPW/NBP ) is an urban Iron Age culture of the Indian Subcontinent, lasting c. 700–200 BC, succeeding the Painted Grey Ware culture and Black and red ware culture. It developed beginning around 700 BC, or in the late Vedic period, and peaked from c. 500–300 BC, coinciding with the emergence of 16 great states or mahajanapadas in Northern India, and the subsequent rise of the Mauryan Empire. After recent excavations at Gotihwa in Nepal, by radiocarbon datings it was found that proto-NBPW is at least from 900 BC. Excavations in India at Ayodhya, Juafardih near Nalanda, and Kolhua near Vaisali, show even earlier radiocarbon datings around 1200 BC. Based on this, the following chronology may be proposed : Proto-NBPW (1200–800 BC); Early NBPW (800–300 BC); and Late NBPW (300–100 BC).
A luxury style of burnished pottery used by elites, it is associated with the emergence of South Asia's first cities since the decline of the Indus Valley Civilization; this re-urbanization was accompanied by massive embankments and fortifications, significant population growth, increased social stratification, and wide-ranging trade networks.
Scholars have noted similarities between NBP and the much earlier 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 also, however, important differences between these two cultures; for example, rice, millet and sorghum became more important in the NBP culture. The NBP culture may reflect the first state-level organization in the Indian Subcontinent.
Some sites where Northern Black Polished Ware have been found are Mahasthangarh, Chandraketugarh, Wari-Bateshwar,Bangarh and Mangalkot (all in Bangladesh and West Bengal, India).
Other NBPW sites, associated with the mahajanapadas, are Charsada (ancient Pushkalavati) and Taxila, in Pakistan; Delhi or ancient Indraprastha; Hastinapura, Mathura, Kampil/Kampilya, Ahichatra, Ayodhya, Sravasti, Kausambi, Varanasi all in Uttar Pradesh; Vaishali, Rajgir, Pataliputra, and Champa in Bihar; and Ujjain and Vidisha in Madhya Pradesh.