Does anyone has an idea why it took so long before playmobil released the confederates 

Hello,
David ...
Back in the early 1980s Playmobil introduced a COLOR set of Confederate soldiers (3611). The set may not have sold very well. And, Zirndorf may have thought that there was not enough interest to warrant the production of Confederatte soldiers at that time.
(What's very interesting is that they really made an attempt at historical accuracy with the coloring of this set. I particularly like the flag, the red kepi and cuffs on the Artillery figure and the Louisiana Tigers.)
All the best (and I love your fotos),
Richard