He reformed the government of Rome and was extremely successful on the battlefield. Under Severus, the Roman Empire reached its greatest extent and he successfully founded a dynasty. ... Severus created a 'military monarchy', marginalized the Senate and his expansion of the army weakened the economy.
Britain. Thus began the War of 1812 (a bit of a historical curiosity, since the United States declared the war and then waited for Britain to come and fight rather than immediately invading or attacking).
It would be Japan, since after the bombs dropped US forced the Emperor to stepped down.
When the Federal Government supported the war effort without imposing wage and price controls. This caused the employment opportunities for women and minorities increased greatly.