The present study forms part of a project to find cleaning and conservation methods that for a certain period of time would provide outdoor bronzes with a protective, durable and attractive surface, able to withstand the Swedish climate. A first part of these efforts has been a study of methods of metal extraction during the 16th and 17th centuries, of procedures for casting cannon and of the subsequent surface treatment. The different environments that the cannon have been subjected to were discussed. The combined effects of these factors were considered as a background to the study of the corrosion damage. The study also summarizes an extensive literature investigation.