Zhu Rongji, the former Chinese premier whose market reforms helped drive the country's rapid economic rise, died of illness in Beijing on Wednesday at age 97, China's state news agency Xinhua reported. Known as China's "economic czar" and the "iron-fisted premier," his reformist legacy has taken on renewed nostalgia in recent years as President Xi Jinping has steered the country toward a more state-controlled, nationalistic economic path. A Reformer Who Reshaped China's EconomyZhu began steering China's economic policy in the early 1990s as vice premier before becoming premier in 1998 at age 69, according to NBC News. Internationally, he was best known for leading China's entry into the World Trade Organization, a process that transformed the country into the world's largest exporter, according to NBC News. Reputation and PersonalityZhu earned the nicknames "Boss" and "Madman Zhu" for his demanding style and willingness to criticize official bungling and corruption, according to NBC News.