The province had been trading with the Chinese since Yuan Dynasty until the first phase of Ming Dynasty in the 13th and 15th century.
Inhabitants of the province were also trading with Japan and India.
A Buddhist image was reproduced in mould on a clay medallion in bas-relief from the municipality of Calatagan.
According to experts, the image in the pot strongly resembles the iconographic portrayal of Buddha in Siam, India, and Nepal. Eighteen years later, a grave was excavated in nearby Punta Buaya.
However, Wang Teh-Ming in his writings on Sino-Filipino relations points out that Batangas was the real center of the Tagalog tribe, which he then identified as Ma-yi or Ma-i.