what's the difference?

[Ironic Honesty]

i have two questions:

1. what's the difference between all of these extra versions and the original invasio barbarorum?

2. how do i download these other versions?

[julianus heraclius]

i have two questions:

1. what's the difference between all of these extra versions and the original invasio barbarorum?

INVASIO BARBARORVM : SOMNIUM APOSTATAE IULIANI
Also known as Imperium Julianorum (IJ). Contains two campaigns based on the exploits of the Emperor Flavius Claudius Iulianus (Julian the Apostate). The main campaign sees him in Constantinople in 361 AD preparing to invade the Sassanids, the seconds sees him as Caesar in Gaul charged with securing Gaul from the Germans.

INVASIO BARBARORVM : RUINA ROMAE
The original INVASIO BARBARORVM, set in 410 AD, with the Goths in the outskirts of Rome, the Vandals in Spain, The Huns sweeping the east like a storm, and all of Gaul under the usurper Constantine III.

INVASIO BARBARORVM : (Rio's) FLAGELLVM DEI
Also known as Rio's IBFD. Featuring two campaigns: 463AD on the decline and the eventual collapse of the Roman Empire in the West; and 432 AD with the Huns on the outskirts of the Empire, and about to conquer the world. Also includes RESTITUTIO IUSTINIANI (Justinian Campaign) as an add-on provincial campaign, with Justinian attempting to reconquer the west.

2. how do i download these other versions?

Each mod has its own download section. Please see each one.