Siege problem

[Grand_Armee]

Sometimes my armies or corps will sit in a province and either intermittently attack the city, or not attack at all. The AI doesn't seem to have this problem, and for me it's like wiring trouble...sometimes you can figure it out, sometimes you can't.

Is there something I need in the army to make it happen?

[Naomi]

The strength of your besieging force relative to the size of the enemy garrision force will determine if any besieging action can take place. That your force drops to a size deemed not sufficient in this regard can be attributed to many factors, such as failure to draw regular supply, unsuccessful foraging, casualty suffered in earlier besieging attempts, and so on. Besieging forces, like any other, receive reinforcements turn after turn as long as they are in supply. In other hand, the (out-of-supply) garrision under siege may suffer from a head loss in defending or starving. Both help the ratio of the two sides' strengths to reach a level to qualify a besieging attempt. I hope I am right.

[vonkohlmann]

You may also be experiencing the multiple province minor country bug. If for example you attack Denmark with it's 4 or so provinces, you often have to declare war every turn even as your troops are trying to besiege a city, or besieged it a previous turn, even though no official peace treaty or cease fire was ever offered. It's a known bug, and there are threads detailing it.

[Naomi]

Agree. Hope war weariness is not among the factors too.