The first few turns of any campaign are critical, especially in hotseat play where you face opponents who are all too able to capitalize on your every mistake. They are also unique in that it is the only part of the campaign where you have close to perfect knowledge of the game board, especially if you're at the top of the rotation. With this in mind, what are some of your favorite opening plays in hotseat campaigns?

I'll start with my thoughts on England in the Britannia campaign:
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In my opinion, the most important thing to do as the English is to keep Ireland and Wales contained. Since neither of those factions have anywhere to expand except through you, you should make use of your first turn advantage to set up an alpha strike against them while they are at their weakest.

The most important move, then, will be to secure your position in Ireland. Setting Dublin as your capital, setting taxes to low, and moving Maurice Fitzgerald from Trim will result in a public order of 70%, which can be brought up to 75 by training a unit of spear militia. Training a spy in Dublin as well will protect Maurice from the lurking Irish assassins, putting their chance of successfully killing him below the threshold allowed by most hotseat rules.

Unfortunately it is completely impossible to hold Derry against King Brian's army in the first turn, so emptying its garrison and sending them east towards Downpatrick is your best bet, potentially hiding them in the woods north of the town to conceal your intentions until it is too late. Simultaneously moving up the garrison of Trim and the nearby fort, you put yourself in the position of having nearly a full stack's worth of troops in range to besiege Downpatrick on turn 2, and out of the range of Irish armies on their turn 1. You can further bolster these numbers by sending the two cavalry units in Dublin north, recruiting a second unit of militia to make up the difference in garrison strength.

At the same time, send the garrisons of the two other forts to meet each other east of the Irish fort near Tipperary, and the garrison of Athenry south towards the town itself recruiting one unit to keep up order. I suggest recruiting the available mercenaries with Maurice to deny them to Ireland and sending those along as well.

A similar strategy can be followed on the mainland against Wales. Besiege their southern fort with the garrison of Cardiff, moving the unit of Feudal Knights from Gloucester to cover the garrison, and besiege the northern one with units from Chester. The cavalry from Oxford and Nottingham, including generals can be joined together with the garrison of Shrewsbuy at the crossroads west of the city, which is within the first turn movement range of the Welsh stack in Montgomery and therefore unavoidably lost turn 1. Again, I suggest hiring up all the mercenaries in the region for this stack, to deny them to the Welsh and bolster your strength to 17 units, with 4 more shortly behind if you empty the garrisons of Oxford and Nottingham, which can be done turn 1 without risking their rebellion.

This strategy is very costly, as you spend most of your starting treasury on mercenaries and extra garrison, which could very easily mean starting turn 2 in the red. It also leaves you somewhat vulnerable to an invasion by Norway since there wont be many troops nearby to support Lancaster. It puts you in a position to strange two of your rival factions early however, before they have a chance to put their superior treasuries to use. The anti-Irish half of this opening is easier than the anti-Welsh half, due to the reinforcements Wales will recieve when they capture Shrewsbury and when you take any of their starting regions. For this reason, I suggest starving Wales out rather than assaulting them, or trying to knock them out all in one go.