The V Iovia was stationed, together to her sister legion VI Herculia, in Pannonia Secunda, a new province created with the segmentation of the old Pannonia province.
The purpose of the legion, having her permanent camp in Bononia and an advanced castellum in Onagrinum, was to protect the imperial residence of Diocletian in Sirmium (Illyricum).
The Notitia Dignitatum locates the legion still in Illyricum at the beginning of the 5th century.
[1] It is possible that some men from this legion and from the VI Herculia formed the Jovians and Herculians, the new imperial bodyguard of Diocletian.
If this identification is correct, V Iovia men had the appellative martiobarbuli, since they were expert in throwing plumbata, small darts carried by five in the inside of their shields.