Who started “My Little Pony bronies”?

Anonymous /co/ users, on Open web, Oct 21, 2010. It reached 5 platforms in 9.8 years.

LineageContestedKey steps, 12 of 16. Lines follow time and platform
Amid Amidi / Cartoon BrewBefore the first postAnonymous /co/ usersFirst postTwilight Sparkle in My Little Pony: Friendship Is MagicSethisto / Equestria DailyOpen webOwner responsePressPlatform jumpPlatform jumpCommercialCommercialBacklashMilestoneAfterlifePatient zero