Why did Imam Hussain (PBUH) rise up ?
Imam Hussain's movement is , indeed , perceivable via two
perspectives.
One perspective involves the appearance of Imam Hussain ’s
action , which is a movement against a corrupt , deviated , suppressive and
oppressive regime : Yazid ’s Regime .
But , at the heart of his action , there is a more important
movement that the second perspective will lead to : the move against ignorance
and humiliation of the mankind .
In fact , even though Imam Hussain fights against Yazid ,
his extensive historical fight is not against the short - living and
insignificant Yazid . Rather , his main fight is against mankind ’s ignorance ,
abasement , deviation and humiliation .
Ayatollah Khamenei
the text from : fairy_4412
http://english.khamenei.ir/news/5942/Who-is-Imam-Hussain-Why-did-he-launch-an-uprising