The document discusses the creation and expansion of empires through history. It covers three main topics: 1) The Spanish conquest of the Incas and Aztecs in South America, which was aided by the Spanish' steel weapons which were stronger than the obsidian and clay weapons of the native tribes. 2) The development of Roman law starting with the Twelve Tables in the 5th century BC and the later codification of Roman laws into codes and compilations by the Eastern Roman Emperor Justinian in the 6th century AD. 3) How Roman civil law focused on governing the Roman people and became the basis for modern public international law.