5 events the sources record for this year, grouped by region.
What happened
China (4)
The Yellow River burst its banks in fifteen places, including Kaifeng, Xiangfu, and Chenliu; more than 200,000 people of Nanjing were released to build embankments. (History of Yuan (Yuanshi), Annals 元史 卷14 世祖 1286年)
The rebellion of Nayan: in 1286 Kublai went to war in person, the only time he did so. (Marco Polo, The Travels (Yule translation) Book II ch. II (Yule 영역 가운데 CONCERNING THE REVOLT OF NAYAN, WHO WAS UNCLE TO T))
At dawn the Great Khan, with his army, climbed a hill and looked down on Nayan's camp on the plain (Nayan's execution is in the next chapter). (Marco Polo, The Travels (Yule translation) Book II ch. IV (Yule 영역 가운데 OF THE BATTLE THAT THE GREAT KAAN FOUGHT WITH NAYA))
After defeating Nayan, the Great Khan returned to his capital, Cambaluc, and held a feast. (Marco Polo, The Travels (Yule translation) Book II ch. VI (Yule 영역 가운데 HOW THE GREAT KAAN WENT BACK TO THE CITY OF CAMBAL))
Korean Peninsula (1)
A report from Chungcheong Province's Taltarhwason, Yi Yeong-ju, says Kang Yun-myeong rebelled and killed Yi Sun, magistrate of Yeongwol. (Goryeosa (History of Goryeo) 世家 卷30 忠烈 十二年)