: 4th century
- 5th century
- 6th century
Decades: 370s 380s 390s 400s 410s - 420s - 430s 440s 450s 460s 470s
Years: 418 419 420 421 422 - 423 - 424 425 426 427 428
- On the death of Honorius, the primicerius notariorum Joannes siezes the throne of the Western Roman Empire, and is declared emperor.