For example, if I have a warrior, an archer and an axeman all fortifying the city, and a quecha attacks the city, who will be defending against the quecha first? Does the counter unit i.e. axeman go first? Or the unit being countered i.e. archer go first?

best defender first. so axeman. unless his health was like 0.5 or something and the archer was full thus making him better. :)

best defender first. so axeman. unless his health was like 0.5 or something and the archer was full thus making him better. :)

So if you have a spearman and an axeman , and enemy has a knight, the axeman will defend first?

umm i dont know as i stay in ancient and am to stoned to go into civpedia to look up stats. Here's an example using random numbers lol.

If the knight had strength 12 and it attacked the game would do the calculation of odds for knight v spearman
i.e if spearman is 4 and +50 v mounted its strength is 6

whereas the axe is 5 and no bonus as knight is not melle so it is 5.

Thus the spearman would defend first.

The unit which has the best chance against the attacker, taking into account all bonuses, promotions and HP levels, will be the defender.

right, the unit with the best odds will defend.

Sometimes this "best defender" is your elite unit you don't want to use to defend, or your medic, so make sure you take these out of your defensive stack.

Usually the unit with the best chance to win, although that unit may be too hurt in which case it will cycle to the next best unit. Which might not be a good thing if its a medic unit or a special unit.

Sometimes this "best defender" is your elite unit you don't want to use to defend, or your medic, so make sure you take these out of your defensive stack.

An interesting point...of course any elite units that are elite because of offensive promotions aren't in my cities while I'm at war.