Liu Hui (ca. 260 AD) #1
Among the very earliest books of mathematics from China is "Jiuzhang suansho," best known in English as "The Nine Chapters on the Mathematical Art." This collection of 246 mathematical problems - divided into nine topics as the title suggests - covers the gamut from practical applications to astronomy, surveying and elementary trigonometry.
The "Nine Chapters" is thought to date to the Han Dynasty (ca. 200 BC) but fragments of some of the problems have been found in earlier works. Liu Hui lived at least 450 years later. But it is copies of his edition of the "Nine Chapters" that have survived and have his undisputed seal on the cover. Today, scholars honor Liu Hui as the most prominent figure in ancient Chinese mathematics.
Please see Liu Hui #2 for a translation of his preface to the Nine Chapters.