He proved extremely efficient, and was soon promoted to quartermaster. This involved extensive traveling, and he started to acquire food shops of his own around Lulong and on the other side of the Great Wall, in Manchuria.

His rapid rise was boosted when he helped General Wang to suppress an uprising in Inner Mongolia. In almost no time he had amassed a fortune, and he designed and built for himself an eighty-one-room mansion at Lulong.

In the decade after the end of the empire, no government established authority over the bulk of the country. Powerful warlords were soon fighting for control of the central government in Peking. Xue's faction, headed by a warlord called Wu Pei-fu, dominated the nominal government in Peking in the early 1920s. In 1911 Xue became inspector general of the Metropolitan Police and joint head of the Public Works Department in Peking. He commanded twenty regions on both sides of the Great Wall, and more than 10,000 mounted police and infantry. The police job gave him power; the public works post gave him patronage.

Allegiances were fickle. In May 1923 General Xue's faction decided to get rid of the president, Li Yuan-hong, whom it had installed in office only a year earlier. In league with a general called Feng Yu-xiang, a Christian warlord, who entered legend by baptizing his troops en masse with a firehose, Xue mobilized his 10,000 men and surrounded the main government buildings in Peking, demanding the back pay which the bankrupt government owed his men. His real aim was to humiliate President Li and force him out of office. Li refused to resign, so Xue ordered his men to cut off the water and electricity to the presidential palace. After a few days, conditions inside the building became unbearable, and on the night of 13 June President Li abandoned his malodorous residence and fled the capital for the port city of Tianjin, seventy miles to the southeast.

In China the authority of an office lay not only in its holder but in the official seals. No document was valid, even if it had the president's signature on it, unless it carried his seal. Knowing that no one could take over the presidency without them, President Li left the seals with one of his concubines, who was convalescing in a hospital in Peking run by French missionaries.

As President Li was nearing Tianjin his train was stopped by armed police, who told him to hand over the seals. At first he refused to say where he had hidden them, but after several hours he relented. At three in the morning General Xue went to the French hospital to collect the seals from the concubine. When he appeared by her bedside, the concubine at first refused even to look at him: "How can I hand over the president's seals to a mere policeman?" she said haughtily. But General Xue, resplendent in his full uniform, looked so intimidating that she soon meekly placed the seals in his hands.

Over the next four months, Xue used his police to make sure that the man his faction wanted to see as president, Tsao Kun, would win what was billed as one of China 's first elections. The 804 members of parliament had to be bribed. Xue and General Feng stationed guards on the parliament building and let it be known that there would be a handsome consideration for anyone who voted the right way, which brought many deputies scurrying back from the provinces. By the time everything was ready for the election there were 555 members of parliament in Peking. Four days before the election, after much bargaining, they were each given 5,000 silver yuan, a rather substantial sum. On 5 October 1923, Tsao Kun was elected president of China with 480 votes. Xue was rewarded with promotion to full general. Also promoted were seventeen 'special advisers' all favorite mistresses or concubines of various warlords and generals. This episode has entered Chinese history as a notorious example of how an election can be manipulated. People still cite it to argue that democracy will not work in China.

In early summer the following year General Xue visited Yixian. Though it was not a large town, it was strategically important. It was about here that the writ of the Peking government began to run out. Beyond, power was in the hands of the great warlord of the northeast, Chang Tso-lin, known as the Old Marshal. Officially, General Xue was on an inspection trip, but he also had some personal interests in the area. In Yixian he owned the main grain stores and the biggest shops, including a pawnshop which doubled as the bank and issued its own money, which circulated in the town and the surrounding area.

For my great-grandfather, this was a once-in-a-lifetime chance, the closest he was ever going to get to a real V.I.P.

He schemed to get himself the job of escorting General Xue, and told his wife he was going to try to marry their daughter off to him. He did not ask his wife for her agreement; he merely informed her. Quite apart from this being the custom of the day, my great-grandfather despised his wife. She wept, but said nothing. He told her she must not breathe a word to their daughter. There was no question of consulting his daughter. Marriage was a transaction, not a matter of feelings. She would be informed when the wedding was arranged.

My great-grandfather knew that his approach to General Xue had to be indirect. An explicit offer of his daughter's hand would lower her price, and there was also the possibility that he might be turned down. General Xue had to have a chance to see what he was being offered. In those days respectable women could not be introduced to strange men, so Yang had to create an opportunity for General Xue to see his daughter. The encounter had to seem accidental.

In Yixian there was a magnificent 900-year-old Buddhist temple made of precious wood and standing about a hundred feet high. It was set within an elegant precinct, with rows of cypress trees, which covered an area of almost a square mile. Inside was a brightly painted wooden statue of the Buddha, thirty feet high, and the interior of the temple was covered with delicate murals depicting his life.

It was an obvious place for Yang to take the visiting V.I.P.

And temples were among the few places women of good families could go on their own.

My grandmother was told to go to the temple on a certain day. To show her reverence for the Buddha, she took perfumed baths and spent long hours meditating in front of burning incense at a little shrine. To pray in the temple she was supposed to be in a state of maximum tranquillity, and to be free of all unsettling emotions. She set off in a, rented horse-drawn carriage, accompanied by a maid. She wore a duck-egg-blue jacket, its edges embroidered in gold thread to show off its simple lines, with butterfly buttons up the right-hand side. With this she wore a pleated pink skirt, embroidered all over with tiny flowers. Her long black hair was woven into a single plait. Peeping out at the top was a silk black-green peony, the rarest kind. She wore no makeup, but was richly scented, as was considered appropriate for a visit to a temple. Once inside, she knelt before the giant statue of the Buddha. She kowtowed several times to the wooden image and then remained kneeling before it, her hands clasped in prayer.

As she was praying, her father arrived with General Xue.

The two men watched from the dark aisle. My great grandfather had planned well. The position in which my grandmother was kneeling revealed not only her silk trousers, which were edged in gold like her jacket, but also her tiny feet in their embroidered satin shoes.

When she finished praying, my grandmother kowtowed three times to the Buddha. As she stood up she slightly lost her balance, which was easy to do with bound feet.

She reached out to steady herself on her maid's arm. General Xue and her father had just begun to move forward.