Who ruled
- The Göktürk interregnum, 630–682 Ashina Simo 639–643
- Western Göktürk Khaganate Üç Tuğlu Khan 638–642 · Irbis Shegui Khan 642–651
- Xueyantuo Khaganate (Syr Tardush) Yinan Khan 628–645
And beyond the steppe
- China Tang Taizong 626–649
- Iran Sasanian Yazdegerd III 632–651 · Rashidun Umar 634–644
- Korea Goguryeo Yeongnyu 618–642 · Bojang 642–668
- Byzantium Heraclian Constans II 641–668
Eastern steppe
-
Environment · Late Antique Little Ice Age: the cold phase the Altai tree rings define from 536 to about 660 (536–660)
Climate and the steppe empires · First Göktürk Khaganate · Avars
The coldest decade in the Altai is the 540s
-
Environment · Lake Telmen stands 4.8 metres above its present level, a humid phase before the drying that follows (600–700)
China
Persia
-
The last Persian army is destroyed at Nihavand; the Iranian plateau is open