Also Asia always was and to my knowledge still is using a lot of IE - not sure about the reason why.
A little history lesson:
* Netscape wanted to dominate the web, gain a monopoly and gain full control.
* IE came late to the party - long after Netscape was already established
* MS invested a *ton* of resources to catch up, rapid development pace, quick updates, constantly new features and improvements
* MS too wanted dominance and full control of the web
* MS gained marked share through "dirty tricks" leveraging their OS dominance
* MS got repeatedly sued for unfair competition, paid large sums, paid lip-service to the courts but never truly changed their strategy
* that hurt Netscape but didn't kill it
* what killed off Netscape was their own doing: a costly code rewrite, that took way to much time and delivered subpar results
* Microsoft won, they had what they wanted: full control of the web, and the power to shape it however they saw fit
* they did nothing. they just stuck with IE6, no new features or improvements for years, even bugfixes and security fixes became really slow. all momentum was lost.
* Firefox rose from the ashes of Netscape - MS still did nothing.
* Firefox gained significant market share - that finally kicked MS into gear
* MS re-started updating and improving IE - but they were technologically behind and had to play catch-up again
* Chrome entered the ring and boosted the pace of development
* IE never fully caught up
* Chrome gained full dominance of the market - but unlike IE did not slow down development
* MS tried all their dirty tricks again - but they still continued to loose market share
* they rebranded IE to Edge (still using the same render engine, but dropping backwards compatibility)
* they dropped their own render engine, and switched to using webkit
* despite even more dirty tricks, no breakthrough success in terms of market share
I believe the fading of IE pretty much started with Microsoft resting on their (un-earned) laurels, after Netscape died. And yes, that's even before IE peaked - while they still had upwards momentum.