leader Nurgaci sought to devise a suitable system that integrated the phonetic Mongolian and Jurchen language. This resulted in the creation of the Manchu language, which would later be deemed one of the greatest inventions that sparked the unification of Manchuria. However, for some time the script was not well received and the Jianzhou continued to use Mongolian as their lingua franca. Relationship with the Joseon dynasty The Korean Joseon dynasty, incepted in the 1300s, had considered some Jurchen headmen as useful allies. Jurchens were positioned as far south as Hamhung in north central Korea since the 12th century. However, the Yi order in Korea included intense military campaigns to drive Jurchens northward toward the Yalu River and ultimately beyond it, into present-day Manchuria. One of the most vivid narratives and depictions of the Jianzhou comes from a passage supplied by Sin Chun-li. Sin Chun-li’s mission to the Jianzhou Jurchens was aimed to resolve the incident of 1594, in which the Jianzhou Jurchens captured at least seventeen Koreans and were being held for ransom. To resolve the issue, Sin was dispatched by the Korean court to Nurgaci's capital at Fe Ala. He and a small party of Korean officials crossed the Yalu river at Mamp Ojin, and followed a tributaries northwest to the Suksu Valley where Nurhaci was based. Sin kept a detailed written record of his journey as he moved through Jianzhou Jurchen confederation. Despite it being winter, his insights tell us that the Jianzhou land was abundant with rivers, forests, and saw industrialization. Sin stratified his findings and stated that the Jianzhou Jurchen divided their society into villages of about twenty households or less, which were clustered along forested riverbanks. They lived off of the river and its surrounding terrain. Relationship with the Ming Dynasty The Jianzhou Jurchens, and other Jurchen groups were often in contention with the Ming and Yi for rights to trade. They often contended at Nurgan and Liaodong, which were politically and culturally marked territories before the Conquest of Qing China. However, there was also simultaneously cohesion, which was reflected in the scheduled visits of Jurchen leaders to Peking to "make ritual obeisance" to the Ming emperor. These visits were to satisfy the Ming tributary system. Conversely, it helped the Ming establish a list of Jurchen elites and military occupancies, but also deescalated tensions between the two groups. Nurgaci conducted at least two of