Excerpts from Books and Wikipedia
"Under the benign rule of the Song dynasty (960-1279), China became the world's most prosperous and technologically advanced country." The Song dynasty ended with the Mongol conquest of 1279. [Furtado: 1001 Days] "The Jin forces captured the Song ruler, Emperor Qinzong, along with his father, the retired Emperor Huizong, and many members of the imperial family of Emperor Taizong's bloodline and officials of the Song imperial court. This event marked the end of the era known as the Northern Song Dynasty, when the Song dynasty controlled most of China. Many members of the Song imperial family, most notably Zhao Gou (later Emperor Gaozong), managed to escape to southern China, where they reestablished the Song dynasty (as the Southern Song dynasty) in the new capital, Lin'an (present-day Hangzhou)." [Wikipedia] The Jingkang Incident occurred in 1125-1127. "The Jurchen soldiers sack Kaifeng, bringing an end to the Northern Song Dynasty in China; the Song moves further south and makes Lin'an their new capital." [Wikipedia: Timeline of Middle Ages]