The Maritime Jade Road was initially established by the animist indigenous peoples between the Philippines and Taiwan, and later expanded to cover Vietnam, Malaysia, Indonesia, Thailand, and other countries. Artifacts made from white and green nephrite have been discovered at a number of archeological excavations in the Philippines since the 1930s. The artifacts have been both tools like adzes and chisels, and ornaments such as lingling-o earrings, bracelets and beads. Tens of thousands were found in a single site in Batangas. The jade is said to have originated nearby in Taiwan and is also found in many other areas in insular and mainland Southeast Asia. These artifacts are said to be evidence of long range communication between prehistoric Southeast Asian societies. Throughout history, the Maritime Jade Road has been known as one of the most extensive sea-based trade networks of a single geological material in the prehistoric world, existing for 3,000 years from 2000 BCE to 1000 CE. The operations of the Maritime Jade Road coincided with an era of near absolute peace which lasted for 1,500 years, from 500 BCE to 1000 CE. During this peaceful pre-colonial period, not a single burial site studied by scholars yielded any osteological proof for violent death. No instances of mass burials were recorded as well, signifying the peaceful situation of the islands. Burials with violent proof were only found from burials beginning in the 15th century, likely due to the newer cultures of expansionism imported from India and China. When the Spanish arrived in the 16th century, they recorded some warlike groups, whose cultures have already been influenced by the imported Indian and Chinese expansionist cultures of the 15th century.