List of Heads of State in 300

List of Heads of State in 299 - 300 - List of Heads of State in 301 - List of Heads of State by Year

Africa

Armenia - Tiridat III , king ( 287 - 330 )
Wakataka - Prazarasena I , Emperor ( 270 - 330 )
Hassanides - al-Harith I ibn Talabah , king ( 287 - 307 )
Gupta - Ghatotkaca , Maharaja ( 280 - 319 )
Dhanyavadi - Thuria Rupa , King ( 298 - 313 )
Western Kshatraps - Viswasena , Mahaksatrap ( 295 - 304 )
Iberia - Mirian III , King ( 284 - 361 )
China ( Western Jin ) -
- Hui-di (Sima Zhong), emperor ( 290 - 307 )
- Empress Jia Nanfeng , Regent ( 291-300 )
- Syma Lun , Regent ( 300 - 301 )
Korea ( Three States Period):
- Kai Confederation - Kogil , Van ( 291 - 346 )
- Goguryeo -
  - Ponsan , Thewan ( 292 - 300 )
  - Michon , Thewan ( 300 - 331 )
- Baekche - Punso King ( 298 - 304 )
- Silla - Kirim , Isagim ( 298 - 310 )
Kushan kingdom - Vasudeva II , king ( 290 - 310 )
Lahmids (Hira) - Imru ul-Qays I ibn Amr , king ( 295 - 328 )
Pagan - Ying Min Pike , King ( 299 - 324 )
Persia (Sassanids) - Narce , Shahinshah ( 293 - 302 )
Rajarat - Mahasena King ( 277 - 304 )
Toba - Toba Luguan , Leader ( 294 - 307 )
Tampa - Fan Yi , Prince ( 284 - 336 )
Himyar -
- Shamir Yukhar`ish , king ( 238 - 300 )
- Yasser Juhan`im II , king ( 300 - 310 )
Chera - Ilamkadungo King ( 287 - 317 )
Japan - Odzin , Emperor ( 270 - 310 )

Kingdom of the Bosporus - Fofors king ( 278 - 309 )
Dumnonia - Karadok , ruler ( 290 - 305 )
Ireland - Fiaha Sribtine , High King ( 285 - 322 )
Roman Empire (Tetrarchy) -
- East -
  - Diocletian , Roman Emperor (Augustus) ( 284 - 305 )
  - Galerius , Roman Emperor (Caesar) ( 293 - 305 )
- West -
  - Maximian , Roman Emperor (Augustus) ( 286 - 305 )
  - Constantius Chlorus , Roman Emperor (Caesar) ( 293 - 305 )
Papal throne - Marcellinus , pope ( 296 - 304 )