Qin and Han: Unification, the Civil Service, the Silk Road
The Qin conquest of 221 BCE and the First Emperor, standardisation, the burning of books, the terracotta army, the Han dynasty and Confucian government, the beginnings of recruitment by merit, the Xiongnu and the Great Wall's early lines, Zhang Qian and the Silk Road, paper (traditionally credited to Cai Lun, 105 CE), and the Han's fall.
One empire, one script
The Qin lasted only fifteen years, but its unification of script, currency, law and measures created the framework of imperial China. The First Emperor's tomb complex near Xi'an, with the terracotta army discovered by farmers in 1974, shows the state's capacity to organise labour. The Han kept Qin institutions but softened them with Confucian ideals; Sima Qian wrote his history under the Han emperor Wu.
The name "Silk Road" (Seidenstrasse) was coined by the German geographer Ferdinand von Richthofen in 1877; the routes themselves were a network, not one road. China's population under the Han was recorded in a census of 2 CE at about 57.7 million, among the earliest surviving census figures anywhere.
Sima Qian, Shiji (trans. Burton Watson, 1961); Mark Edward Lewis, The Early Chinese Empires: Qin and Han (2007); Valerie Hansen, The Silk Road: A New History (2012).