Culture or time period
- Yayoi culture (ca. 300 BC–ca. 300 AD)17
- Year of the Four Emperors (68–69 AD)40
- Yiddish2
- Yine19
- Yocha Dehe Wintun Nation243
- Yokaiah Pomo20
- Yokaya21
- Yokuts1,706
- Yolngu people (N117.1)43
- Yomud2
- Yoruba1,575
- Yoruba cluster1,575
- Yosa division of Matilours indians2
- Yuan dynasty (1271–1368 AD)1
- Yuki1,180
- Yukpa28
- Yuman250
- Yuman II1
- Yup'ik223
- Yuracare1