Who invented the Holden commodore?

The original Commodore was adapted in Australia from a European Opel design, with items such as independent rear suspension replaced by simpler parts, the old Holden "Red" 6 cylinder and V8 engines fitted, and some strengthening done for Australian roads. Subsequent Commodores to VZ have also been based on Opels to greater or lesser extents, with Australian and American engines fitted, among other differences. VE is an Australian design.