Julius will not run without the original Caesar 3 files. 'Julius is a fully working open-source version of Caesar 3, with the same logic as the original, but with some UI enhancements, that can be played on multiple platforms. It took 10 years for this project to reach completion, a MASSIVE undertaking by Bianca van Schaik, a god amongst men. The goal of Julius is to remake the game from scratch so that it is possible to run it on current computers and into the future, with some UI enhancements. Many parts of this guide has been made OBSOLETE thanks to the Julius & Augustus open-source projects. I never play Caesar III without Augustus, trust me, you want to read this!