On a mountainside above the Southwestern China city of Kunming, a wooden courtyard home sits, with a wushu martial arts practice room, tunnels leading to a network of rooms dug out of the mountain, a stone tower with slits for marksmen and a room where Chiang Kai-shek and his wife spent eight nights in the darkest days of 1941.

This was the weekend villa of the 'Emperor of Yunnan,, Lung Yun, who ruled the province with an iron fist from 1927 until 1945. It was a critical period of China's history – reunification under Chiang and World War II, in which Lung played a major role. He kept the Japanese army out of Yunnan, built a 974-km road to Burma and turned Kunming into an important base for the war effort. It was the centre of the 'Flying Tigers', which flew 800,000 tons of military supplies from India.

Historians describe Lung as a man of great physical strength who exercised each day and lived in a modest style, with a long robe his favored dress. Like many of his class and wealth, he smoked opium. Of his six wives, four had children.

But there is nothing to tell the visitor who used to live in the courtyard home. After Lung left in 1945, it was used as an army barracks, pigsty, food and chemicals factory and a restaurant. None of his belongings or a single photo remains.

"In China, we wipe out the history of the former dynasty," said Wang Min, working there to turn the home into a museum of traditional China. "Lung served under the Nationalists, so he has been wiped out of history. Every dynasty does this."

It is the same story at the beautiful nine-hectare estate in downtown Kunming, where Lung lived with his six wives. With trees, gardens, lakes and two-storey villas, it is a miniature Diaoyutai. It has been turned into the Zhenzhuang state guest house. Its visitors have included Queen Elizabeth II of Britain, King Harald V of Norway, Henry Kissinger and Communist Party leaders from Beijing. A new building with 187 rooms built in 2007 is open to the public, with the presidential suite costing 15,000 yuan a night.

But visitors find no name, photo or statue of its former owner. "The teachers in school told us nothing about Lung Yun," said one of the staff. "We learned about Mao, Zhu De and the Communist leaders. If I were not working here, I would not know about him."

At Kunming's largest Xinhua bookshop, a member of the history section said they had had no biography of Lung since 2005. "In our schools, children learn of national and not local history. It is a countrywide curriculum. The teachers do not speak of Lung Yun."

Lung was born on November 19, 1884, the son of a slave-owning landlord and official in Zhaotong county in northeast Yunnan. The family was of Yi nationality. His father died when he was four and he went to live with his uncle. He had little interest in study but took up martial arts. He became a pupil of a wandering master and developed a high level of ability.

In 1911, he joined the army of the local warlord and studied cavalry warfare at a military academy in Kunming. He rose through the ranks and earned the confidence of Tang Jiyao, the governor of Yunnan and head of its army, becoming a corps commander. In February 1927, he and an associate staged a coup, overthrowing Tang, who died on May 22.

He became the commander of the 38th army under Chiang Kai-shek's command and, at Chiang's request, arrested dozens of Communist party members and leftist sympathizers. He became 'emperor' of Yunnan for the next 18 years.

For a career soldier with limited education, he was an unusually enlightened ruler. He reformed the tax system and stabilized the province's finances. He encouraged manufacturing, especially textiles and production of coal and non-ferrous metals, of which Yunnan has rich reserves.

He turned a tin company in Gejiu into what has now become the Yunnan Tin Group, one of the biggest producers in the world, with annual sales of six billion yuan, 615,000 employees and two listed subsidiaries. He saw the importance of transport in a landlocked, mountainous province. When he took office, Yunnan had fewer than 40 kilometers of paved road and a railway line, built by the French, to Hanoi. He oversaw construction of six highways to the neighboring provinces of Guizhou, Sichuan and Guangxi.

Previously, Yunnan had relied on imports from Vietnam to provide sufficient grain. Lung increased the area under cultivation, reduced the tax burden on farmers and built warehouses; he made the province self-sufficient in grain, even with the substantial increase in population during the anti-Japanese war.

He invested heavily in education, at the primary, secondary and tertiary level, for both Han and minority people. He supported Yunnan's first university, a private institution named Donglu University. In 1934, it became the state-owned Yunnan University, with colleges in literature, law, engineering, medicine and agriculture.

In 1937, Lung invited Xiong Qinglai, a professor from Qinghua University in Beijing and one of China's best-known scholars, to become chancellor. Xiong brought with him a large number of talented professors who made Yunnan University a national institution.

He built a professional army of 200,000 men, using training methods from Japan and arms and equipment imported from Europe. He ran Yunnan as his own empire, excluding officials of Chiang's government in Nanjing, one reason for the Generalissimo's dislike of him.

Another was that he allowed Communist Party members and left-wing people to operate and did not permit Chiang's secret police to arrest them. In December, 1938, Wang Jing-wei passed through Kunming after his escape from Chongqing en route for Hanoi. A personal friend, Lung allowed him free passage. He would later head the pro-Japanese government in Nanjing.

But, in his hostility to Japan, Lung stood together with Chiang. In September 1937, he sent 40,000 troops 1,000 kilometers north to confront the victorious Japanese army in Hunan. It was a dangerous move for a provincial warlord to commit a fifth of his army so far from home. They arrived at Taierzhuang at a critical moment. The Chinese army was in danger of being over-run. Lung's men helped to turn the tide and win the first major victory over the Imperial Japanese army, a vital psychological boost for China after a string of demoralizing defeats. In the 20-day battle, the Yunnan army lost 20,000 dead and wounded.

For the next eight years, Lung succeeded in keeping his province in Chinese hands. Another great achievement was construction of the road to Burma, which he proposed to Chiang in 1937. The route, 974 km long and with 370 bridges, was completed in September 1938, after nine months' labor by tens of thousands of workers using the most basic tools. Three thousand died and nearly 10,000 were left injured or handicapped.

The western world marveled at this 'miracle.' Only could China complete such a Pharaonic project. It was the only land route open between China and the outside world throughout the war. Over the next seven years, it carried over 2,000 vital materials into China; in 1942, 100,000 Chinese troops went the other way to join the Allied forces in Burma fighting the Japanese. Lung also began construction of a railway line to Burma but had to stop half-way through because Japanese victories there made it impossible to acquire the necessary materials and equipment.

With Chongqing, Kunming became one of the two principal bases of the war effort. Tens of thousands of Chinese officials, soldiers, professionals and students poured into the city to escape the Japanese. It was the eastern base of the 'Flying Tigers,' a squadron under the command of American General Claire Chennault, and, the Air Transport Command, which flew goods over the Himalayas from India.

Between May 1942 and September 1945, the ATC brought 800,000 tons of war material over what became known as "the hump." They lost 609 planes, an average of 15 a month, with 1,500 airmen killed or missing over some of the world's highest mountains at 6,000 meters.

The victory over Japan in August 1945 should have been Lung's finest hour. But, in Chinese politics, you survive only if you are stronger than the one standing behind you; Chiang chose this moment to move against him. He ordered Lung's army to Vietnam to take the surrender of the Japanese army and plotted his dismissal with one of his top subordinates.

He organized banquets and dances at Lung's palace, to keep him happy and off balance. On October 3, 1945, Chiang's soldiers surrounded Kunming; Lung had only limited forces of his own in the city, who were forced to hand over their weapons. Lung escaped from his palace, took refuge with loyal troops and refused to surrender. He only agreed when Prime Minister T.V. Soong came in person to negotiate.

After 18 years of unchallenged power in Yunnan, he was flown to Chongqing, where he began three years of house arrest. His war record and contributions to Yunnan counted for nothing. Chiang appointed a new governor of Yunnan and sent his army to Manchuria to fight the Communist armies under Lin Biao.

In December 1948, Lung was finally able to escape to Hong Kong, where he joined a pro-Communist party and voiced public support for the new regime. After curing his life-long opium addiction, he moved in January 1950 to Beijing, where he was warmly received and given a senior position in the Ministry of Defense – but he had no power, because the Communists did not trust him. He was given a monthly salary of 500 yuan – an enormous sum at that time – as well as a driver, secretary, bodyguard, cook and servants. He visited the Soviet Union, Romania and Yugoslavia.

In the spring of 1957, he was declared a 'rightist', stripped of his posts and had to write a self-criticism. He died of a heart attack on June 27, 1962. The very next day, the United Front Department removed his designation as a rightist; senior figures attended his funeral, praised him for a glorious life in the service of the nation and the police, and placed his remains in the Babaoshan cemetery, the resting place of the Communist leadership. He was formally rehabilitated in June 1980. His children left China; his descendants live abroad, mostly in the United States.

In 2005, Central Television declared him to be 'one of the most influential Chinese of the 20th century'.