The provinces that may be raided are:
- Neighbouring provinces. You get the gold and prestige immediately.
- Provinces where you have ships in adjacent sea zones (or major rivers, for Germanic pagans). The loot will be transferred to the fleet, and will be added to your treasury when the fleet docks.
The target must have a different religion. (This restriction is either removed or limited to Hindus(??) in patch 18.104.22.168, in beta at the time of writing.)
To raid, simply set troops into raiding mode by clicking the "Toggle Raiding" button. This may only be done in friendly territory. Armies containing mercenaries cannot raid.
Raiding free loot
Even a small band of raiders can ransack the countryside for loot. The base available loot in a province is roughly 2/3 of the total annual income for all holdings in that province. Of this loot:
- some is protected by walls. The protected amount is equal to the sum of the fort levels in all (un-sacked) realm holdings
- the remainder may be looted freely, by leaving raiding troops in the province
The speed of looting depends on the size of your raiding party (up to 500) and the "max loot" in the province (regardless of whether it is protected by fortifications or already plundered). It takes 100 days to fully loot a province, although your raiders will usually have to pause when they encounter fortifications.
Loot every 4 days = (Max loot) × min(Raiders, 500) × 0.04
Sacking a holding:
- Loots a large amount of money (roughly double the annual income of the holding). The formula is:
Looted Gold = (1.5 * Holding Base Income) + (0.02 * Total Buildings Cost)
- Lets more of the free loot be gathered.
- Cause a penalty on demesne income and prevents from sacking again for 3 years.
- Has a 10% chance of destroying a random building in that holding.
- Has a 5% chance of destroying the holding entirely, if the holding has less than 4 buildings. The capital holding can't be destroyed.
- Always destroys any building or holding currently being constructed.
- Has a chance of imprisoning any courtiers in the province.
- May trigger an event giving the Viking trait, if raider's religion is Germanic or reformed Germanic.
- May trigger some special raiding event chain.
Germanic pagans are the best raiders
- 769 start date: the "Viking Age" begins in 793, giving independent rulers of Norse culture free shipyards in all realm provinces with the correct culture. Coastal provinces in the independent ruler's demesne (not held by vassals) also get free shipbuilding technology.
- 867 start date: only Germanic pagans begin with ships.
- Germanic pagans have the unique ability to navigate major rivers such as the Rhine
Raid rich provinces
- Use the economy map mode to identify rich provinces
- Within tribal areas, the provinces worth raiding are the ones with temples (holy sites)
- Consider distant targets such as Venice
- Come back after the loot bar refills
- Sacking gives a large lump sum of holding loot, frees additional province loot for raiding, and captures courtiers
- Focus on with provinces with city/church capitals (e.g. merchant republics)
- If your religion allows taking concubines, consider distant targets such as Constantinople
- Come back after 3 years
- AI rulers will not raise levies in provinces where you currently have troops, even if they outnumber you
- Each liege (duke, king, emperor) should be weak or distracted by war
Flee when threatened
- Appoint a commander with the Organizer trait
- Retreat into ships
- If caught in a hopeless battle, order retreat (right-click a destination) rather than waiting for morale to drop
Raid and sack before war
- This lets you take on a sequence of small armies, rather than one large army, because:
- Enemies will not have the aid of allies during the raid.
- Enemies must gather their levies from scratch, while yours are already gathered.
- Enemies (AI) will not raise troops in provinces where you have troops.
- If your army is large enough, you can even sack the holding with the levies still unraised, killing them without a battle.
- Remember that getting 100% warscore requires winning a "major battle" or occupying all enemy territory.
Raid and sack during war
- Use a single army in "raid mode", then switch to "occupy mode" immediately after sacking (and order a fast assault).
- Or, put both a "raid army" and an "occupy army" in a province, with the raid army arriving first. Immediately after sacking, order both armies to move out, then order the occupy army to stay.