William Wallace.

[Ethien]

I'm currently playing a campaign as England. I've kicked the Scots out of Scotland, so they survive with two provinces in France. What are the conditions for him to spawn? I'd like to know so I can depart with more force from the island, or have to keep an army behind to worry about the Scottish super army coming.

[DC53]

It's an event, he spawns at certain turn and has to be at war with England. I only got two stacks of Highland troops when I was playing as Scotland though. On the other hand, I used those stacks to take Winchester and London. On a crusade, no less.

[Thasinta]

It's an event, he spawns at certain turn and has to be at war with England

So, essentially, taking the Scots out prevents him from spawning, as long as it's done before that turn? Or will he still arrive (as a Rebel, then, I suppose)?

[kraxmause]

So, essentially, taking the Scots out prevents him from spawning, as long as it's done before that turn? Or will he still arrive (as a Rebel, then, I suppose)?

No, he has several spawning triggers, take a look at the campaign script:

Spoiler Alert, click show to read: 

;============== William Wallace Uprising ================

declare_counter wallace_spawned
set_counter wallace_spawned 0

monitor_event FactionTurnStart FactionType scotland
and I_TurnNumber = 60
and I_NumberOfSettlements scotland < 4

set_counter wallace_spawned 1

terminate_monitor
end_monitor

monitor_event FactionTurnStart FactionType scotland
and I_NumberOfSettlements scotland < 2

set_counter wallace_spawned 1

terminate_monitor
end_monitor

monitor_event GeneralCaptureSettlement FactionType england
and TargetFactionType scotland

set_counter wallace_spawned 1

terminate_monitor
end_monitor

monitor_event PreFactionTurnStart FactionType scotland
and I_CompareCounter wallace_spawned = 1

spawn_army
faction scotland
character William Wallace, named character, age 20, x 55, y 253, direction SE, battle_model Wallace_General, portrait wallace, label scotland4wallace
traits MilitaryInclination 1 , Military_Edu 2 , NaturalMilitarySkill 2 , GoodCommander 1 , ScotlandHero 1 , LoyaltyStarter 1, BattleChivalry 2 , Loyal 2 , Just 2 , Rabblerouser 3 , Hardened 1
unit Highland Nobles exp 4 armour 0 weapon_lvl 1
unit Highland Nobles exp 2 armour 0 weapon_lvl 1
unit Highlanders exp 3 armour 1 weapon_lvl 1
unit Highlanders exp 3 armour 1 weapon_lvl 1
unit Highlanders exp 3 armour 1 weapon_lvl 1
unit Highland Pikemen exp 4 armour 1 weapon_lvl 0
unit Highland Pikemen exp 4 armour 1 weapon_lvl 0
unit Highland Pikemen exp 3 armour 1 weapon_lvl 0
unit Highland Pikemen exp 3 armour 1 weapon_lvl 0
unit Highland Nobles exp 3 armour 0 weapon_lvl 1
unit Highland Nobles exp 3 armour 0 weapon_lvl 1
unit Noble Highland Archers exp 1 armour 1 weapon_lvl 0
unit Noble Highland Archers exp 1 armour 1 weapon_lvl 0
unit Noble Highland Archers exp 1 armour 1 weapon_lvl 0
unit Highland Rabble exp 3 armour 0 weapon_lvl 0
unit Highland Rabble exp 3 armour 0 weapon_lvl 0
unit Highland Rabble exp 4 armour 0 weapon_lvl 0
unit Highland Rabble exp 4 armour 0 weapon_lvl 0
unit Border Horse exp 2 armour 0 weapon_lvl 0
unit Border Horse exp 2 armour 0 weapon_lvl 0
end

spawn_army
faction scotland
character random_name, named character, age 26, x 55, y 253
traits MilitaryInclination 1 , Military_Edu 2 , NaturalMilitarySkill 2 , GoodCommander 1 , LoyaltyStarter 1, BattleChivalry 2 , Loyal 2 , Just 2 , Rabblerouser 3 , Hardened 1
unit Highland Nobles exp 4 armour 0 weapon_lvl 1
unit Highland Nobles exp 2 armour 0 weapon_lvl 1
unit Highlanders exp 3 armour 1 weapon_lvl 1
unit Highlanders exp 3 armour 1 weapon_lvl 1
unit Highlanders exp 3 armour 1 weapon_lvl 1
unit Highland Pikemen exp 4 armour 1 weapon_lvl 0
unit Highland Pikemen exp 4 armour 1 weapon_lvl 0
unit Highland Pikemen exp 3 armour 1 weapon_lvl 0
unit Highland Pikemen exp 3 armour 1 weapon_lvl 0
unit Highland Nobles exp 3 armour 0 weapon_lvl 1
unit Highland Nobles exp 3 armour 0 weapon_lvl 1
unit Noble Highland Archers exp 1 armour 1 weapon_lvl 0
unit Noble Highland Archers exp 1 armour 1 weapon_lvl 0
unit Noble Highland Archers exp 1 armour 1 weapon_lvl 0
unit Highland Rabble exp 3 armour 0 weapon_lvl 0
unit Highland Rabble exp 3 armour 0 weapon_lvl 0
unit Highland Rabble exp 4 armour 0 weapon_lvl 0
unit Highland Rabble exp 4 armour 0 weapon_lvl 0
unit Border Horse exp 2 armour 0 weapon_lvl 0
unit Border Horse exp 2 armour 0 weapon_lvl 0
end

historic_event scotland_wallace event/william_wallace.bik
terminate_monitor
end_monitor

monitor_event FactionTurnStart FactionType scotland
and IsFactionAIControlled
and I_CharacterExists scotland4wallace
and not I_SettlementOwner Edinburgh = scotland

if I_SettlementUnderSiege Edinburgh
siege_settlement scotland4wallace, Edinburgh, attack
terminate_monitor
end_if

siege_settlement scotland4wallace, Edinburgh, maintain

if I_SettlementOwner Edinburgh = scotland
terminate_monitor
end_if

end_monitor

[Loco Mike]

Not to sure, if i remember right its a year that makes him appear. Either case keep up with your expansion of Norway

EDIT - Just build some forts & store some top notch mercs. For 2000 coin, that will let you store 8 units for free.

[DC53]

Not to sure, if i remember right its a year that makes him appear. Either case keep up with your expansion of Norway

EDIT - Just build some forts & store some top notch mercs. For 2000 coin, that will let you store 8 units for free.

Storing units in forts frees them of upkeep??

[Loco Mike]

Storing units in forts frees them of upkeep??

Yes, 2 units to each fort. You can change this but its to powerfully to increase i think. Its even more powerful in other mods that use Britannia Campaign stone forts

[Gabrius]

You can store up to 2 units in a fort with free upkeep, the rest will have regular upkeep.