|424 by topic|
|Ab urbe condita||1177|
|Balinese saka calendar||345–346|
|Chinese calendar||癸亥年 (Water Pig)
3120 or 3060
— to —
甲子年 (Wood Rat)
3121 or 3061
|- Vikram Samvat||480–481|
|- Shaka Samvat||345–346|
|- Kali Yuga||3524–3525|
|Iranian calendar||198 BP – 197 BP|
|Islamic calendar||204 BH – 203 BH|
|Minguo calendar||1488 before ROC
|Seleucid era||735/736 AG|
|Thai solar calendar||966–967|
550 or 169 or −603
— to —
551 or 170 or −602
|Wikimedia Commons has media related to 424.|
Year 424 (CDXXIV) was a leap year starting on Tuesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Castinus and Victor (or, less frequently, year 1177 Ab urbe condita). The denomination 424 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
- October 23 – Emperor Theodosius II nominates his cousin Valentinian, age 5, the imperial title nobilissimus Caesar ("most noble") of the Western Roman Empire. He is betrothed to his own daughter Licinia Eudoxia, who is only 2 years old.
- Roman usurper Joannes sends Flavius Aetius, governor of the Palace (cura palatii), to the Huns to ask for their assistance. After negotiating, he returns back for Italy with a large force.
- Winter – A Roman army under command of Ardaburius leaves Thessalonica (modern Central Macedonia) and marches for Northern Italy, where they make their base at Aquileia.
- Shao Di, age 18, is deposed by a group of high officials and succeeded by his younger brother Wen Di as emperor of the Liu Song Dynasty. Shao is exiled to Suzhou, and later killed by an assassin.