The 1642 Kaifeng flood ( during the 3rd Battle of Taifeng ), caused by breaches of the Yellow River dykes by both sides, ended the siege of Kaifeng and killed over 300, 000 of its 378, 000 residents.

Some of the largest cities in the world were found in China during this period ( Kaifeng and Hangzhou had populations of over a million ).

With a population of over 1, 000, 000 people, a culture of hospitality and a paper currency, Kaifeng was ripe for the development of restaurants.

* In the Song Dynasty capital of Kaifeng, the number of registered people within the walls is 1, 050, 000 ; the army stationed there boosts the overall populace to some 1. 4 million people.

It was recorded that each year before 1101 AD, the prefecture of Xinan ( modern Xi-xian, Anhui ) alone would send 1, 500, 000 sheets of paper in seven different varieties to the capital at Kaifeng.

The population of Shanghai increased from 12, 000 households to over 250, 000 inhabitants after Kaifeng was sacked by invading armies.

Today, 600-1, 000 residents of Kaifeng trace their lineage back to this community.

Daily life of people from the Song period at the capital, Bianjing, today's Kaifeng.

* The Song Dynasty Chinese capital city of Kaifeng has some half a million residents by this year ; including all those present in the nine designated suburbs, the population is over a million people.

This came about after the conquest of northern China by the Jurchen people ( see Jin Dynasty ) in 1127, while the Chinese court fled south from Kaifeng to Hangzhou.

The last census revealed about 400 official Jews in Kaifeng, now estimated at some 100 families totalling approximately 500 people.

Kaifeng was one of the largest in the world at this time and it was full of various kinds of shops and heavy traffic from people coming in and leaving the city.

The History of Jin 《 金史 》 ( compiled by 1345 ) states that in 1232, as the Mongol general Subutai ( 1176 – 1248 ) descended on the Jin stronghold of Kaifeng, the defenders had a " thunder-crash bomb " which " consisted of gunpowder put into an iron container ... then when the fuse was lit ( and the projectile shot off ) there was a great explosion the noise whereof was like thunder, audible for more than a hundred li, and the vegetation was scorched and blasted by the heat over an area of more than half a mou.

The Jurchens tried to resist ; but when Kaifeng was attacked, Āizōng fled south.

The Jin Dynasty was forced to submit and pay tribute to the Mongols as vassals ; when the Jin suddenly moved their capital city from Beijing to Kaifeng, the Mongols saw this as a revolt.

The Mongols were at one time allied with the Song, but this alliance was broken when the Song recaptured the former imperial capitals of Kaifeng, Luoyang and Chang ' an at the collapse of the Jin Dynasty.

But the Jurchen kept their main capital further north, until 1214, when they were forced to move the imperial court southwards to Kaifeng in order to flee the Mongol onslaught.

In 1938, when the Imperial Japanese Army captured Kaifeng, the government led by Chiang Kai-shek bombed the Huayuankou dam in Zhengzhou in order to prevent the Japanese forces from advancing further.

He was found after Emperor Gaozong lost his only child and heir and thus ordered the administration to look for all the descendants of the imperial family all across southern China ( all the close relatives of Gaozong had been captured by the Jurchen invaders when they entered the capital Kaifeng during their conquest of northern China in 1127 ).

In China, due to the political situation, research on the Kaifeng Jews and Judaism in China came to a standstill until the beginning of the 1980s, when political and economic reforms were implemented.

* 1221, the Thundercrash Bombs, used by the Jin invaders during the attack of Qizhou, which were exploding grenades filled with black powder rather than incendiary bombs filled with molten material, and lastly in 1232 when the Jin repelled the Mongolians in the battle of Kaifeng.

After the battles of Luoyang and Kaifeng, the Ming government was unable to stop Li's rebellion, as most of its military force was involved in the battle against the Manchurians in the north.

Capitals: of the Song Dynasty, Kaifeng and Lin ' an ; of the Liao Dynasty, Shangjing, Nanjing, and Tokmok ; of the Jin Dynasty, Shangjing, Zhongdu, and Kaifeng ; of the Western Xia Dynasty, Yinchuan

In 960, the Song Dynasty gained power over most of China and established its capital in Kaifeng ( later known as Bianjing ), starting a period of economic prosperity, while the Khitan Liao Dynasty ruled over Manchuria, present-day Mongolia, and parts of Northern China.

The Jin Dynasty took power over northern China and Kaifeng from the Song Dynasty, which moved its capital to Hangzhou ( 杭州 ).

Outside Europe, the escapement mechanism had been known and used in medieval China, as the Song Dynasty horologist and engineer Su Song ( 1020 – 1101 ) incorporated it into his astronomical clock-tower of Kaifeng in 1088.

A Song Dynasty ( 960 – 1279 ) chancellor of China, Wang Dan ( 957 – 1017 ), lost his eldest son to smallpox and sought a means to spare the rest of his family from the disease, so he summoned physicians, wise men, and magicians from all across the empire to convene at the capital in Kaifeng and share ideas on how to cure patients of it.

* 1127 – Invading Jurchen soldiers from the Jin Dynasty besiege and sack Bianjing ( Kaifeng ), the capital of the Song Dynasty of China, and abduct Emperor Qinzong and others, ending the Northern Song Dynasty.

Food catering establishments which may be described as restaurants were known since the 11th century in Kaifeng, China's northern capital during the first half of the Song Dynasty ( 960 – 1279 ).

The Iron Pagoda of Kaifeng, Song Dynasty China, built in 1049 during the reign of Emperor Renzong of Song.

* 1028: the King of Srivijaya appeals to the Song Dynasty Chinese, sending a diplomatic mission to their capital at Kaifeng.

* The Jurchen Jin Dynasty in China defend Kaifeng against Mongol invaders, involving the use of rockets.

* January – March – In Song Dynasty China, scholars and farmers demonstrate around Kaifeng for the restoration of a probity military official, Li Gang ( 李綱 ).

However, the poor performance and military weakness of the Song army was observed by the Jurchens who immediately broke the alliance with the Song, launching an invasion into Song territory in 1125 and another in 1127 ; in this latter invasion, the Jurchens captured not only the Song capital at Kaifeng, but the retired emperor Huizong, his successor Qinzong, and most of the Imperial court.

From there, he pushed the Jin army back north as far as Kaifeng.

Although his army, under Linghu Chao, was numerous, it was unable to make further territorial gains due to the failure to wrest control of Yongqiu ( modern Qi County, Kaifeng, in Henan ) and ( later ) the nearby Suiyang District from the Tang defenders led by Zhang Xun.

Sun Bin proposed the strategy of " besieging Wei to rescue Zhao " and the Qi army attacked the Wei capital city of Daliang ( present-day Kaifeng ), forcing the Wei army to turn back to save the city and effectively lifting the siege on Handan.

( For example, after the death of Liu Xuanzuo ( 劉玄佐 ) the military governor of Xuanwu Circuit ( 宣武, headquartered in modern Kaifeng, Henan ) in 792, Emperor Dezong was initially intending to commission his granduncle Wu Cou ( 吳湊 ) to replace Liu, but after Xuanwu soldiers mutinied and supported Liu Xuanzuo's son Liu Shining ( 劉士寧 ), Emperor Dezong did not dare to confront the Xuanwu army and instead agreed to commission Liu Shining.

A scale model of Su Song's Astronomical Clock Tower, built in 11th century Kaifeng, China.

* 1094: the astronomical clock tower of Kaifeng, China — engineered by the official Su Song — is completed.

* The Iron Pagoda of Kaifeng, China is built in 1049.

* New city of Bian ( 汴 ) constructed on the site of Kaifeng in China.

* Estimation: Constantinople, capital of the Byzantine Empire, becomes the largest city of the world, taking the lead from Kaifeng, capital of China.

* January 9 – Jurchen forces sack the Song Chinese capital of Kaifeng ( the Jingkang Incident, 靖康事變 ), and begin more than a century of political division between northern and southern China.

* The Chinese polymath statesman and scientist Su Song has the successful pilot model for his astronomical clock tower constructed in Kaifeng, China.

* Estimation: Kaifeng, capital of China becomes the largest city of the world, taking the lead from Córdoba in Al-Andalus.

He pays a huge ransom and then abandons Northern China, heading for Kaifeng.

* Construction of the large Iron Pagoda in Kaifeng, China, is completed in this year during the Song Dynasty.

* The Song Dynasty Chinese scientist and statesman Su Song publishes his Xin Yi Xiang Fa Yao, a treatise outlining the construction and operation of his complex astronomical clocktower built in Kaifeng, China.

During the Mongol Yuan Dynasty ( 1271 – 1368 ) the capital of China was moved to Beijing, eliminating the need for the canal arm flowing west to Kaifeng or Luoyang.

During the Northern Song (, 960 – 1127 ), the Song capital was in the northern city of Bianjing ( now Kaifeng ) and the dynasty controlled most of inner China.

The Jurchen conquest of northern China and shift of capitals from Kaifeng to Lin ' an was the dividing line between the Northern Song Dynasty and Southern Song Dynasty.