11 events the sources record for this year, grouped by region.
What happened
China (6)
Daizong died in the inner hall of Zichen Hall and left an edict for the crown prince to ascend before the bier. (Old Book of Tang (Jiu Tangshu), Annals 舊唐書 卷11 大歷14年 5月)
In May 779, that night the emperor (Daizong) dies in the Zixin inner palace, and by testamentary edict Guo Ziyi concurrently holds the post of Grand Councilor. (Zizhi Tongjian (Comprehensive Mirror) 권225 779년 항)
Tibetans and Nanzhao join forces of 100,000 men and invade Shu along three routes; prefectures and counties fall one after another. (Zizhi Tongjian (Comprehensive Mirror) 資治通鑑 卷226)
Korean Peninsula (1)
In the fourth month a whirlwind rose at the tomb of Kim Yusin, entered the tomb of King Michu and complained; King Hyegong apologized and gave thirty gyeol of meritorious estate. (Samguk Yusa (Memorabilia of the Three Kingdoms) 紀異第一 末鄒王 竹葉軍)
Japan (2)
The Bohai envoy Chang Sonsu reports that Goryeo envoys were shipwrecked, and that they built two ships and followed him to court. (Shoku Nihongi (Continued Chronicles of Japan) 續日本紀 卷第35 「丙午。渤海使張仙壽等」)
An imperial order to the Dazaifu: the Silla envoy Kim Nanson and others came with a New Year tribute, but they are to be questioned on their reasons for entering court, including whether they carry a letter case. (Shoku Nihongi (Continued Chronicles of Japan) 續日本紀 卷第35 「冬十月乙巳。勅大宰府」)
Western Europe (2)
In spring Charles moves from Heristal to Compiègne, and on the way back Hildibrand, Duke of Spoleto, comes out to meet him with great gifts (Royal Frankish Annals ARF(Einhard판) a.779, Kurze 1895 p.53)
After the Duria assembly Charles crosses the Rhine at Lippeham and at a place called Buochold drives off the Saxons who resisted in vain hope. He subdues Westphalia and camps for several days at Mimidulli on the Weser, receiving hostages and oaths from the Angrarians and Ostphalians (Royal Frankish Annals ARF(Einhard판) a.779, Kurze 1895 p.55)