How did Xi Xia become connected to the Mongol Empire after the first Mongol attacks?

In 1209, the Tangut state of Xi Xia secured its connection to the Mongol Empire by pledging its allegiance to Genghis Khan.1

By obtaining this submission, Genghis Khan effectively neutralized Xi Xia as a potential threat on his flank, which allowed him to focus his military efforts on preparing for an invasion of the Jin dynasty in northern China. This strategic move ensured that he did not have to contend with a hostile power in the northwestern region while his main forces were engaged elsewhere. The Xi Xia dynasty remained under Mongol influence until it was ultimately conquered by Mongol troops in 1227, the same year Genghis Khan died during a campaign against the state.1234