Guangyun in the context of "Qieyun"

A rime dictionary, rhyme dictionary, or rime book (traditional Chinese: 韻書; simplified Chinese: 韵书; pinyin: yùnshū) is a genre of dictionary that records pronunciations for Chinese characters by tone and rhyme, instead of by graphical means like their radicals. The most important rime dictionary tradition began with the Qieyun (601), which codified correct pronunciations for reading the classics and writing poetry by combining the reading traditions of north and south China. This work became very popular during the Tang dynasty, and went through a series of revisions and expansions, of which the most famous is the Guangyun (1007–1008).

These dictionaries specify the pronunciations of characters using the fanqie method, giving a pair of characters indicating the onset and remainder of the syllable respectively.The later rime tables gave a significantly more precise and systematic account of the sounds of these dictionaries by tabulating syllables by their onsets, rhyme groups, tones and other properties. The phonological system inferred from these books, often interpreted using the rime tables, is known as Middle Chinese, and has been the key datum for efforts to recover the sounds of early forms of Chinese. It incorporates most of the distinctions found in modern varieties of Chinese, as well as some that are no longer distinguished. It has also been used together with other evidence in the reconstructions of Old Chinese.

The Ashina (Chinese: 阿史那; pinyin: Āshǐnà; Wade–Giles: A-shih-na; Middle Chinese: (Guangyun) [ʔɑʃi̯ə˥nɑ˩]) were a Turkic tribe and the ruling dynasty of the Göktürks. They rose to prominence in the mid-6th century when the leader, Bumin Qaghan (died 552), revolted against the Rouran Khaganate. The two main branches of the family, one descended from Bumin and the other from his brother Istämi, ruled over the eastern and western parts of the Göktürk confederation, respectively, forming the First Turkic Khaganate (552–603).

Helian Bobo (Chinese: 赫連勃勃; Middle Chinese Guangyun: [xɐk-li̯ɛn˩ bʰuət-bʰuət]; 381 – c. September 425), né Liu Bobo (劉勃勃), with the epithet Qujie (屈孑), was the founder of the Xiongnu state of Xia, which rose to prominence during the Sixteen Kingdoms period. He belonged to the Tiefu (鐵弗) branch of the Xiongnu, was a descendant of the southern chanyu Liu Qubei, and the son of Liu Weichen, its chieftain. After his father was killed by Northern Wei and the tribe collapsed, Liu Bobo sought refuge with Moyigan, a Xianbei chieftain of Later Qin, and married Moyigan's daughter. As an adult, noted for his imposing stature, eloquence, and intelligence, he won the favor of Emperor Yao Xing of Later Qin, who appointed him a general and placed more than thirty thousand men from the Tiefu and other tribes under his command.

In 407, after Later Qin made peace with Northern Wei, Liu Bobo rebelled. Claiming descent from the Xia dynasty royal line, he styled himself Heavenly King of Great Xia and Grand Chanyu and adopted the era name Longsheng (龍昇), marking the establishment of the Xia state. He spent the following years roaming the northern steppe, deploying cavalry offensives against Later Qin and Southern Liang in the Shuofang region.