Between 481 BC and 221 BC, the Period of the Warring States in China ended by King Zheng of the Qin dynasty succeeding in defeating six competing factions and thus becoming the first Chinese emperor, titled Qin Shi Huang. A ruthless but efficient ruler, he raised a disciplined and professional army and introduced a significant number of reforms, such as unifying the language and creating a single currency and system of measurement. In addition, he funded dam constructions and began building the first segment of what was to become the Great Wall of China to defend his realm against northern nomads. Nevertheless, internal feuds and rebellions made his empire fall apart after his death in 210 B.C.