The time between 481 B.C. and 221 B.C. was the Period of the Warring States in China, which ended when King Zheng of the Qin Dynasty succeeding in defeating six competing factions, thereby becoming the first Chinese Emperor, titled Qin Shi Huang. A ruthless but efficient ruler, the Emperor raised a disciplined and professional army, and introduced a significant number of reforms, 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. However, his empire fell part when he died in 210 B.C. due to internal feuds and rebellions.