The UK industrialized first.
From an interview with EurActiv:
EurActiv: Who is most responsible for climate change – all of us equally or are some people more responsible than others?
Hansen: For fossil fuels use we have very good statistics. The US is responsible for 26% of the excess CO2 in the atmosphere, and China for 10%. The parts of the world that industrialised first are most responsible. The UK is number one, the US is number two and Germany is third.
The UK is Number One to thank for delaying the next Ice Age.