As communist cadres go, Wang Lequan and his successor Zhang Chunxian represent two extremes.
Wang, 65, earned the nickname 'the emperor of Xinjiang ' for his iron-fisted rule over the restive region, and for his fiery rhetoric.
After deadly riots in the region's capital, Urumqi, in July, in which most of those killed were Han Chinese, he appeared on television calling the riot 'a massive conspiracy' to sabotage ethnic unity and called on citizens to 'point the spear towards hostile forces at home and abroad'.
Zhang, on the other hand, is famous for his populist style and his media savvy. When he was transport minister, he would patiently answer questions from reporters who buttonholed him at the National People's Congress. In 2006, he made a tearful appearance on television during a visit to the parents of a university student who died trying to save people from drowning.
Wang cut his teeth as a rural cadre and climbed up the political ladder in his native Shandong province, where he was appointed vice-governor in 1989. In 1991 he was made deputy head of the Xinjiang government and in 1995 was promoted to party secretary.
Wang's tenure in the province was unusually long. Since the 1990s, very few party secretaries in other provinces have served longer than two terms, or 10 years. The central government has shuffled leading cadres between provinces to avoid corruption and nepotism.
Tibet, another border region deemed crucial for ethnic stability, is on its fourth party secretary since 1992. Zhang Qingli, a close ally of President Hu Jintao , was appointed in 2006. Wang's obsession with stability earned him another nickname - 'the secretary of stability'. Political observers believe he remained in office so long because Beijing was reluctant to make changes lest it cause instability in the border region, which is perceived as China's frontline against Uygur separatism and terrorism.
In 1997 Wang presided over a crackdown on Uygur separatism. When riots erupted in the city of Yining after police arrested dozens of Muslims, and young Muslims battled police and attacked Han residents, police responded with force. Officials reported nine deaths, but an Amnesty International report concluded that hundreds, possibly thousands lost their lives or were seriously injured.
Subsequently, many were executed and others jailed and 'illegal' mosques and unauthorised religious classes shut down.
In 2002, Wang was given a seat on the powerful Politburo, the party's inner sanctum. He has since become an important adviser to the central government on ethnic policies.
In 2003, on his watch, Beijing labelled as terrorist organisations four groups linked to the movement to forge an independent state of East Turkestan in Xinjiang. Wang vowed to severely punish all terrorists in Xinjiang. His rigorous style won him the trust of Beijing. Announcing his new role yesterday, Vice-President Xi Jinping praised him for his staunch anti-terrorist efforts.
But everything changed with the riots in July last year, when Han residents in Urumqi publicly showed their anger at the authorities' failure to put down Uygur violence.
In contrast to his predecessor, Zhang, 57, is known for his tact and publicity skills. A manager in a machinery factory, he became assistant to the Yunnan governor in 1995 before a transfer to the Transport Ministry in 1997. In 2002, at age 49, he became the youngest minister in the cabinet when he was appointed transport minister. His marriage to famous CCTV anchor Li Xiuping has boosted his public image.
If he shows his populist style can work in Xinjiang, observers believe Zhang stands a good chance of following Wang into the Politburo.