Ok, after restarting what feels like 50 times I will post my walkthrough for Alaric Campaign A Kingdom of Our Own here. I watched a speed run on YouTube which gave me some tips but I’m a “slow and steady” player so be prepared for the long haul here. The trick is not to build Castles in the enemy bases until the very end:
Note: Top of map diamond is North
First land all your units on the opposite bank, move all but one villager north towards the burned market, move the remaining villager south. Put all military units back onto transport ships and move them to the junction in the river just south of Sarus’ camp. Unload them onto the south west bank at the junction.
Meanwhile, have you villagers build two town centres, one on the ruins next to the stone and lumber camps, and another where your other villagers is to the south, next to the stone as well; you will need to buy stone and wood for this from the market. Get one villager from the main lot of villagers to build a blacksmith nearby (more wood from Market). While the military units are moving research Blast Furnace (buy resources from Market) ASAP.
Return to your military units and move them along the south bank of the river until you get to the ice bridge to Sarus camp. You will be greeted with watch towers, ignore, heading straight through the town centre until you see the forage bushes, turn east and you will see the Sarus unit. Head straight for him and get all units to attack him. You can let one champion or huskarl attack the onager that appears to the east, but continue to attack Sarus until he is dead. The castle will fall and Sarus’s camp will resign. You may have 3 or 4 units left, move them to the very east of the island to be picked up by your transport ships and placed back at camp. Keep restarting until you get Sarus first, otherwise you’re gonna have a bad time.
You villagers will have built your town centres now, so you can boom. And I mean BOOM. Strive for 30 new villagers, making sure you have at least 10 on food, 10 on stone, 10 on wood. Any leftovers get to building straight away. Buy food from Market to get started.
Take a spare villager and walk them along the same way as your military units did to Sarus but once you get to the ice bridge, make them head south until you get to Western Roman Empire’s base. Build 3 gates in succession at the entrance to their camp next to the watch tower. Once built, lock the gates. Move that villager to build a mining camp next to the gold near the Narbo outpost. You shouldn’t have to deal with the WRE for the rest of the game.
At your main base, get a few builders to wall off the entrance to camp, see where on DeeDar Fan’s Speedrun video. Pallisade walls won’t be enough, gotta be gates my friend.
DO NOT BUILD A CASTLE UNTIL YOU CAN DEFEND IT.
I think the first attacks from Narbo of your base are triggered when you build your first castle, so build your gate wall and then castles.
Build two barracks near your castle and start training 4 trebuchets and 20 huskarls. Once spawned, move this group to just beyond your walls to the north to attack the Valentia castle outside their walls. Keep the huskarls on your trebuchets to protect them, but you shouldn’t get any grief from that castle as long as you keep your distance. A light peppering with your trebuchets should have it gone in no time.
Attacking Valentia:
Make sure you have at least 20 huskarls at your home base to protect your western gate from Narbo’s battering rams. Build a castle inside your gate wall to protect you. Garrison the home huskarls in your Castles to be dispatched when necessary.
Do not ignore your economy, you should be aiming for more villagers to sustain the constant spawn of army needed to attack bases while defending your own. It’s not a bad idea to have at least 5 villagers on gold at this stage. You should have 50 villagers by now, mostly on food.
Bring 5 villagers north with you once Valentia castle is gone, build two barracks parrallel with where the castle was. Have the huskarls and trebuchets nearby to protect your villagers. Once built, train 20 more huskarls. While being created turn your first group onto the two towers oustide Valentia’s eastern gate while your trebuchets get to work on destroying the gate. Have your huskarls defending the trebuchets against Valentia’s army that will stream out steadily. Once the gate is destroyed, you can move your huskarls in (now bolstered by just spawned ones) and attack the closest watch towers.
Move the trebuchets to destroy the castle while continuing to spawn from your recently built barracks. Valentia will have a steady stream of Knights, Light Cavalry, Spearmen, and Scorpions. Concentrate on mounted units first, then scoprians and spearmen.
Keep spawning huskarls as your economy allows and once the second castle is destroyed, you can move on to their town centre.
The speedrun video mentioned above has you building castles as soon as you get inside the walls to make them surrender, but Valentia and Narbo are nothing you can’t handle with a strong economy and a steady stream of your army.
Once Valentia is raized, move your villagers at your barracks to move into Valentia and build your own gates in place of Valentia’s. Build a lumber camp next to their eastern one, take over their farms with a mill and their gold with a mining camp.
Those pesky Tolosa tossers will have started attacking you at Valentia once the second castle is destroyed, so make sure your huskarls are out to meet them. By this point, start training Halberdier, as they are strong against Tolosa’s Cavaliers. Don’t build a Castle in Valentia yet. Keep an army of at least 20 mostly halberdiers outside Valentia’s western gate to fend off Tolosa.
Keep the Market in Valentia so you can trade for gold with Trade Carts.
Attacking Narbo:
Once Valentia resigns, WRE switch to enemy. Your locked gates will now be in their way, but they won’t attack them straight away. By the end only one gate was destroyed, the other two stayed put, so WRE shouldn’t bother you (Thanks DeeDar Fan ^.^).
If you haven’t already, build enough houses to host 210 population, as stated in the hints.
Move your trebuchets out of Vallentia back to your base, near you western castle. Build 2 Barracks and 2 stables near the castle and start spawning Cavaliers and Huskarls, plus more trebuchets to get to 6. Continue to train cavaliers and huskarls to replenish those that fall at Narbo (RIP).
Wait to attack until after one of their small groups with battering rams attack. Let your castle deal with them, then move 20 cavaliers, and 30 huskarls with your 6 trebuchets to Narbo’s northern gate. I suggest moving until you trebuchet can just see their archery ranges just inside the walls then get them to attack Narbo’s Gate.
Have 5 Huskarls protect your trebuchets while the rest and your Cavaliers pick off the Arbalestas and Hussars outside the walls. Once the trebuchets have burned the gate, turn them to the watch towers, then the archery ranges. Once the gate is gone, move your army inside to assist the trebuchets while picking off Narbo’s army.
Move the Trebuchets in to get rid of watch towers and any building that spawns enemy units, including town centre and dock. Have your Cavs round up errant villagers in and outside the walls (by which I mean kill), especially the lumber camp to the west, while the huskarls get rid of watch towers and new enemy military units.
Once Narbo is but a shadow of what it used to be, move some villagers in to make new gates and take over the Narbo farms. Try to keep the market so you can train trade carts and get more gold (my huskarls got excited and destroyed it while I wasn’t looking -_-).
Attacking Tolosa:
Move all your military units from your main base and Narbo into a central spot in Narbo, while setting gather points for the Stables, Barracks and Castle to Narbo. Your Barracks near Valentia and your stables should be gathered just outside your Valentia western gate taking on Tolosa’s trebuchet groups.
Build a Monastery in Narbo or Valentia and research Faith, Tolosa have bare monks yo. Train min 3 monks and have them go with our army to Tolosa.
Train groups of 20 halberdiers, 10 Huskarls and 10 Cavaliers with 6 trebuchets from Narbo and move them to the furthest Narbo outpost( if still standing) or next to the Monastery outside the gate.
The strategy for Tolosa is similar to the other two, take the southern gate first with trebuchets while your army attacks Tolosa’s coming out of the gate. Move your trebuchets in when the gates are down and have your army attack Tolosa’s army with your monks nearby to heal. Move your army from Valentia into Tolosa to help. Have your Narbo units and any home base units move into Narbo too. Have trebuchets attack watch towers, the town centre and then spawning buildings, making a dent in their stables will help.
Tolosa will send out their trebuchets, take your Cavaliers to meet them, try to avoid Tolosa’s castle as you move north into their base. Eventually you will have cleared a path so your trebuchets will be safe to attack their castle. Get’er done and continue to immobilise Tolosa until they’re no longer a threat.
Building your Castles
As Tolosa Falls, have your villagers in the enemy bases build a castle in the flagged area. Once that’s done, move those villagers into Tolosa and build your Castle in the flagged area.
Et Voila!
It seems risky to leave Tolosa to the end, but I tried Valentia first then on to Tolosa first and got KOd.
I don’t know exact unit/army numbers, I’m usually not paying attention to numbers of individual units. I’m sure you’ll get the gist of what’s needed.