I was looking at the maps I've submitted and I realized that I've submitted 2 Siege That maps and about 10 invasions but no sieges! This siege is quick and fairly difficult, it took me a few times to beat. The story goes something like this:
The king and the pig are at war over something niether of them remembers. A minor lord responsible for stone and ore mining for both kingdoms you had hoped to remain neutral, and have succeeded for a number of years. Unfortunately, all good things must come to an end, the pig, hoping to sieze control of your iron and stone mines has sent his army to destroy and pillage your castle. After a very long siege both armies inside and out are running very low on food and other supplies. The pig's general, desperate to break the siege before his men desert decides to launch an attack on your castle rather than risk the chance that his men might abandon him for lack of food.