Normally to increase your amount of generals you must increase the number of male family members.One way of doing this is by approving marriages or marrige proposals to the female members of the family.If a proposal is made to one of your male family members then you loose that member of the family to the faction that proposed.As far as I am aware captains cannot become generals no matter how well they perform on the battlefield.When developing a generals traits it is important to consider how that genereal acts after battle.If a general takes a settlement and then exterminates the populace then he acquires a dread trait.Generals with high dread traits tend not to fair so well in governing settlements where generals with high chivalry tend to fair out better.I have generals with high dread traits who do all the fighting and I have generals who do the governing(high chivalry traits).The AI generates the marrige proposals so its not actually possible to create a general you can only develop one.The amount of generals you have is really luck of the draw and how many proposls you accept or reject.Hope this helps.
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