Now I seem to have another problem.
For a while the war was going well. I pushed right and Greek pushed left on Germany. I figure even if I take Berlin it would starve and flip eventually cause I'm not at a point where I can wipe it out, and I don't have the tech to cross ocean yet. So I let Greek take Berlin. But inexplicably Greek accepted a peace offer right after, even though it could have wiped out Germany with sheer number. That got me really worried. Greek was lagging behind me in tech but it has absolute numbers so I cannot fight it. So I had to gift critical techs and cities to placate it. I kept on pushing right and secured that portion of the land, but by now Germany has riflemen, cannon, zepplin and machine gun and I cannot crack it. I tried to ask for peace with Germany. It won't become my vassal, and refuse to give any meaningful tech, but I'm still worried about Greek DoW on me so I accepted. Now with railway online I feel I can soon take on Greek, but I found out Germany became Sitting Bull's vassal. Why does it do that? So maybe I should not give Germany peace, as Sitting Bull is less likely to go to war with me by accepting Germany as vassal? Anyway this really worries me as Germany is way ahead of me in tech, Sitting Bull now has two vassals with vast land, even if I take out Greek Sitting Bull could run away.
So should I keep after war tech and wipe out Greek or should I pull back and race Sitting Bull for tech? Thanks.