> The reason Chrome even exists today is because the US & EU governments forced Microsoft to support other software and companies better.
Chrome came well after Firefox (2008 versus 2002). Many people were fed up with IE due to poor security and performance and were evangelising Firefox online.
> Mozilla has produced its own browser, called Firefox, that is enjoying a surge in popularity as increasing numbers of people and organisations tire of the security problems that plague Microsoft's Internet Explorer.
http://news.bbc.co.uk/1/hi/technology/3680942.stm
You could always install your own browser on Windows. There was nothing ever stopping you from downloading another browser and running it on Windows (in fact Opera at the time IIRC was doing well in Germany). Firefox was simply better than IE and people started using it.