The domination - S. M. Stirling

Originally published as three separate volumes, S.M. Stirling's masterly alternate history tells of the rise to power of the Domination of the Draka and its long struggle with the American-led Alliance for Democracy. Beginning in the rich subcontinent of South Africa, the people calling themselves the Draka - disaffected refugees from the American Revolution - first forged an empire of inconceivable wealth and savagery, founded on conquest and slavery. Spanning the whole of the African continent, the Great War of the early twentieth century gave it much of Asia as well. Then in the Eurasian War, Germany and the Soviet Union exhausted one another and the Draka stepped in, leaving the Domination triumphant from the English Channel to the China Sea. Only America and its allies stands between the Draka and their dream of an enslaved planet.
By the 1990s the Draka commanded the stuff of life itself, mastering biotechnology until they could create new species at will - and transform themselves into the Master Race of their savage dreams. Meanwhile the Alliance for Democracy travelled another path, into the mysteries of the physical universe and the knowledge to be gained there. The final confrontation would settle which was the more powerful . . . or it would leave the earth a lifeless rock on which nothing human remained but bones.