This is a list of pamphlet wars in history.
For several centuries after the printing press became common, people would print their own ideas in small pamphlets somewhat akin to modern blogs.
[1] While these could not be widely available via the internet they could "go viral",[2] because others were free to reprint pamphlets they liked, and therefore ideas were widely spread.
[3] Counter-arguments would then be printed in opposing pamphlets, which might become popular themselves.
A prolonged debate carried out this way changed society many times, until copyright laws effectively banned the propagation of ideas in this way.