Linfen

City · c. 306 CE · in Central Asia

Capital of Former Zhao (306–329).

San Marino (301 CE): Capital of Republic of San Marino (1797–1799).
Kanchipuram (c. 283 CE): Capital of Late Pallava Empire (283–805).
Ye (c. 337–576 CE): Capital of Later Zhao (337–351), Northern Qi (555–576).
Ji (c. 337 CE): Capital of Former Yan (337–370).
Al-Hirah (c. 270–602 CE): Capital of Lakhmid Kingdom (270–602).
Wiryeseong (c. 347 CE): Capital of Baekje (347–660).
Jeju (c. 263 CE): Capital of Tamna (263–1278).
Cologne (c. 261 CE): Capital of Gallic Empire (261–274).
Palmyra (c. 261–1929 CE): Capital of Palmyrene Empire (261–269).
Washim (c. 260 CE): Capital of Vakataka Kingdom (260–500).

Around the same time and place

Three Kingdoms period (220–280 CE): After the end of the Han, China was divided among the states of Wei, Shu and Wu.
Goguryeo (c. 37 BCE – c. 668 CE): Kingdom traditionally founded by Jumong in 37 BCE that grew to rule northern Korea and Manchuria.
Baekje (c. 18 BCE – c. 660 CE): Kingdom in southwestern Korea, traditionally founded in 18 BCE, a conduit of culture and Buddhism to Japan.
Wang Xizhi (303 CE – 361 CE): Calligrapher of the Eastern Jin, revered as the "Sage of Calligraphy".
Gungnae (c. 3–427 CE): Capital of Goguryeo (3–427).