In these few pages, you'll find detailed information for every campaign in the game.
You may also find detailed specific walkthroughs within the article of the campaign.

"The single player campaign follows the story of Princess Zoe as she attempts to wrest the kingdom of Tandarin away from usurpers and restore it to its former glory. The first maps of the campaign also serve as a tutorial about the features and play of Settlers 7. We recommend that new players start with the campaign for that reason. After mastering the campaign you will be ready for the greater challenges of skirmish and multiplayer games. "