Duc-Sum Li was a Shou knight and healer who was the Regent of the Xiousing District in Marsember. He was a descendent of Emperor Li of the Shou Dynasty of Might. He was still active in his extreme old age in 1479 DR, exercising and meditating daily.
In his old age, Duc-Sum had a long white mustache and beard that hung down to his waist.
Duc-Sum was a skilled enough fighter to open his own dojo in Xiousing. He also had skills as a healer, which may have been due to his knowledge of traditional Shou medicine rather than divine magic.
In 1419 DR, Duc-Sum was traveling through Cormyr with his son when he was summoned to heal young Prince Foril I who had fallen gravely ill. King Azoun V was so grateful that he knighted Duc-Sum and granted him control over a new piece of land in Marsember that had been exposed by the drop in the Sea of Fallen Stars' water level. The land was settled by Shou immigrants and became known as Xiousing.