Abstract Containing some of the most extensive phyletic language diversity in mainland Southeast Asia, southern China is primarily home to four language families (phyla), namely Kra-Dai (Tai-Kadai), Hmong-Mien, Sino-Tibetan, and Austroasiatic. By combining geographical data with recent work on phylogenetic linguistics, I will present hypotheses about language origins and dispersals. Possibilities for genetic relationships and extensive borrowings among these various phyla will also be discussed. In this presentation, maps will be extensively used to illustrate the "big picture" of linguistic prehistory in southern China. Geographical evidence strongly points to the Kra-Dai and Hmong-Mien language families as having spread through upstream riverine dispersals in southern China, which parallels Sidwell & Blench's (2011) Austroasiatic riverine dispersal theory. Distributionary evidence strongly suggests that Kra-Dai had dispersed via the Pearl River drainage basin (comprising Guangdong and Guangxi provinces), with the primary branches Kra, Kam-Sui, and Tai each dispersing via different tributaries. On the other hand, distributionary evidence suggests that Hmong-Mien had dispersed via the Xiang River basin, which comprises southeastern Guizhou and most of Hunan province. This is line with Ratliff's (2010) observation that the Proto-Hmong-Mien homeland is located just south of the Yangtze River, based on reconstructions for floral and faunal vocabulary. Rice agriculture was the most likely impetus for both the Kra-Dai and Hmong-Mien dispersals (Blench 2008; Ratliff 2010). Meanwhile, Tibeto-Burman diversity lies mainly in the southwest, suggesting that Tibeto-Burman had diversified and spread from regions located west of China. Two Austroasiatic branches, Palaungic and Mangic, are also widely distributed across Yunnan province (Sidwell 2009), with geographical evidence pointing to their origins south of China. I have also mapped out geographical coordinates for the Angkuic subgroup of Palaungic, which strongly suggest that it had dispersed via the Mekong River drainage basin. Additionally, I will propose two major linguistic areas in southern China, which I will call Southwest Plateau and Lingnan. The Southwest Plateau linguistic area is characterized by the loss of final obstruents and a tendency for multisyllabic lexical forms, is centered in Guizhou and surrounding regions, and comprises language branches such as Hmongic, Tujia, Western Kra, and "Old Southwestern Sinitc" ("Macro-Bai"). Meanwhile, the Lingnan linguistic area is characterized by the preservation of final obstruents and a tendency for monosyllabism, is centered mainly in Guangdong and Guangxi, and comprises Mienic and most Kra-Dai branches.