Emperor Wu, born Yuwen Yong, was perhaps the most capable ruler of the Northern Dynasties. He spent the first twelve years of his reign as a puppet of his cousin, the powerful and ruthless regent Yuwen Hu. Showing incredible patience and cunning, he waited for the perfect moment in 572 AD to assassinate the regent and finally take control of the state himself. His personal life was noted for its extreme austerity; he refused to wear luxurious imperial robes and preferred to sleep on a simple mat like his common soldiers.
His most significant contribution to Chinese history was the formalization and expansion of the 'Fubing' (Garrison Militia) system. This system integrated the military into the agrarian society, creating a class of professional warriors who farmed their own land and provided their own equipment, making the Northern Zhou army both self-sufficient and fiercely loyal. To further strengthen the state, he initiated a massive persecution of Buddhism and Taoism, forcing millions of monks and nuns to return to civilian life where they could pay taxes and serve in the army, thus gathering immense resources for conquest.
Under his command, the disciplined forces of Northern Zhou launched a brilliant invasion of the rival Northern Qi dynasty in the east. In 577 AD, he seized the Qi capital of Ye, effectively unifying the entire North under one banner. He was a man of action who personally led his troops into battle and shared their hardships. Just as he was making grand plans to invade the South and reunite all of China, he fell ill and died suddenly at the age of 35. Though he did not live to see a unified China, his reforms and military successes directly paved the way for his successor-to-be, Yang Jian, to found the Sui Dynasty and complete the task.