I want to know the answer to the following question:
Who was Britain's last serious rival after Napoleon?
All the background I'm provided with is that "Alongside the formal control it exerted over its own colonies, Britain's dominant position in world trade meant that it effectively controlled the economies of many countries, such as China, Argentina and Siam, which has been characterised by some historians as "Informal Empire".". Is that enough to answer the question?
Answer: no