Qin Dynasty ~ 221 BC - 207 BC Major Advancements: The First Highway System, Standard Weights and Measures, National Written Language. Major Public Works:The Great Wall, The Terracotta Army Qin Shihuangdi 221-210 BC Er Shi 210-207 BC During what is referred to as "The Warring States Period" ( over 500 years ), China was divided into over a dozen separate kingdoms which were constantly at war. Borders moved, smaller feudal states were absorbed by larger ones, until eventually one state ( Qin ) became the most powerful. In 221 BC the Qin state defeated the last of its rivals. The leader of the Qin state, declared himself Qin Shihuandi. The First Emperor of China. Qin had successfully unified China and began the longest period of rule by a single political system the world has known. Among his great accomplishments are The Great Wall of China, The Terracotta Army, and over 4,000 miles of highways which connected the Capital with distant provinces. Qin also introduced standardized weights and measures. Even the width of the axles on carts and carriages was standardized so they would ride in the same ruts in the roads. The written characters of the many different regions were simplified, and the first national written language was established. Chinas first bureaucratic administration was also created. From this administration came many harsh new laws including the mandatory burning of all books from the conquered states. Because of the massive demands placed upon the population to create his public works, and his many unpleasant new laws, the dynasty was short lived. Within 15 years the government had collapsed and a period of feudalism and civil war followed. China was once again reunited by the Han.