The Olympics-driven detente has triggered a flurry of diplomatic activity, which culminated in the shock announcement last week that US President Donald Trump had agreed to meet the North's leader Kim Jong Un. The separation follows a dispute about some tiny islands on their unified flag.
In the biathlon - which combines skiing and shooting - the Americans took gold and silver in the women's sit ski, with Kendall Gretsch coming first and Oksana Masters second.
North Korea's first Winter Paralympians did not appear alongside South Korea's team, as happened at the Winter Olympics opening ceremony, after a row over the blue-and-white Korean unification flag.
The competitions for athletes with disabilities became more popular following World War II, offering veterans who had been injured during wartime a chance to compete.
In an opening address, International Paralympic Committee (IPC) president Andrew Parsons urged the Paralympians to "keep fighting, play fair, have fun and keep pushing your limits".
The athletics lineup includes alpine skiing, biathlon, cross-country skiing, ice hockey, snowboarding and wheelchair curling.
The first official Paralympic Games took place in 1960, in Rome, Italy, with 400 athletes representing 23 different countries. Cnossen is a former Navy Seal who lost both legs in an explosion in Afghanistan.
The Pyeongchang Winter Paralympics were officially opened on Friday night with a glittering ceremony that included fireworks and light shows. 14 Belarusian athletes went to Pyeongchang to perform in two disciplines: ski races and biathlon.
Team Japan athletes wave miniature flags during the opening ceremony.