independent centre of refined pottery production that has been well documented on the basis of excavated burial gifts, deposited between 400 BCE and 100 CE in coastal north-western Java. The objects and artefacts of the Buni tradition are known for their originality and remarkable quality of incised and geometric decors. Its resemblance to the Sa Huỳnh culture and the fact that it represents the earliest Indian Rouletted Ware recorded in Southeast Asia are subjects of ongoing research. Early historical era Austronesian maritime trade network The first true maritime trade network in the Indian Ocean was the Austronesian maritime trade network initiated by the Austronesian peoples of Island Southeast Asia. They established trade routes with Southern India and Sri Lanka as early as 1500 BCE, exchanging material culture (like catamarans, outrigger boats, sewn-plank boats and paan) and cultigens (like coconuts, sandalwood, bananas and sugarcane). The trade network also connected the material cultures of India and China, as well as constituting the majority of the Indian Ocean component of the spice trade. Indonesians in particular were trading in spices (mainly cinnamon and cassia) with East Africa using catamarans and outrigger boats and sailing with the help of the Westerlies in the Indian Ocean. This trade network expanded to reach as far as Africa and the Arabian Peninsula, resulting in the Austronesian colonization of Madagascar by 500 CE. It continued through historic times, later becoming the Maritime Silk Road. This trade network also included smaller trade routes within Island Southeast Asia, including the lingling-o jade and trepanging networks. In eastern Austronesia, various traditional maritime trade networks also existed. Among them were the ancient Lapita trade network of Island Melanesia; the Hiri trade cycle, Sepik Coast exchange and Kula ring of Papua New Guinea; the ancient trading voyages in Micronesia between the Mariana Islands and the Caroline Islands (and possibly also New Guinea and the Philippines); and the vast inter-island trade networks of Polynesia. Indianised kingdoms By around 500 BCE, Asia's expanding land and maritime trade led to socio-economic and cultural stimulation and diffusion of mainly Hindu beliefs into the regional cosmology of Southeast Asia. Iron Age trade expansion also caused regional geostrategic remodelling. Southeast Asia was now situated at the convergence of the Indian and the East Asian maritime trade routes, a basis for economic and cultural growth. The concept of "Indianised kingdoms", a term coined by French scholar George Cœdès, describes how