Centuries:	6th century · 7th century · 8th century
Decades:	610s 620s 630s 640s 650s 660s 670s
Years:	641 642 643 644 645 646 647

644 by topic v • d • e

Politics

State leaders - Sovereign states

Birth and death categories

Births - Deaths

Establishment and disestablishment categories

Establishments - Disestablishments

644 in other calendars

Gregorian calendar	644 DCXLIV
Ab urbe condita	1397
Armenian calendar	93 ԹՎ ՂԳ
Bahá'í calendar	-1200 – -1199
Berber calendar	1594
Buddhist calendar	1188
Burmese calendar	6
Byzantine calendar	6152 – 6153
Chinese calendar	癸卯年十一月十六日 (3280/3340-11-16) — to — 甲辰年十一月廿七日 (3281/3341-11-27)
Coptic calendar	360 – 361
Ethiopian calendar	636 – 637
Hebrew calendar	4404 – 4405
Hindu calendars
- Vikram Samvat	699 – 700
- Shaka Samvat	566 – 567
- Kali Yuga	3745 – 3746
Holocene calendar	10644
Iranian calendar	22 – 23
Islamic calendar	23 – 24
Japanese calendar
Korean calendar	2977
Thai solar calendar	1187
v • d • e

Events

By Place

Asia

• The Tang dynasty of China begins the invasion of Goguryo.
• Uthman Ibn Affan succeeds Umar as caliph.

Births

• Li Qiao, Chinese poet and official (d. 713)

Deaths

• Paulinus of York, bishop of Northumbria
• November — Umar, second caliph of Islam (by assassination)