SHAFAQNA – When Moawieh died, Yazid ordered his agents to ask all the people to declare their allegiance to him even Imam Hussain (AS), Abdullah ibn Zubair and Abdullah Omar and the other distinguished individuals. When Imam Hussain (AS) went to see the ruler of Medina, in the presence of Marwan ibn Hakam objected to this and said: In this case, it must be said: We came from God and we will return to God and must say goodbye to Islam because the Islamic Ummah has been forced into having a ruler like Yazid and I heard myself from the Prophet of Allah (PBUH) who said: Caliphate is Haram to Al-e-Sufyan .
From Imam’s sayings, it is clear that Imam Hussain (AS) considered Moawieh’s caliphate void and a satanic rule because the Prophet (PBUH) declared Haram the caliphate by the family of Abu Sofyan. Therefore Imam Hussain (AS) considered Moawieh as someone who usurped the caliphate and declared that Moawieh’s rule was against religious laws and illegal. Moawieh tried to adjust his appearance according to religion but Yazid did not believe in Islam and used to openly oppose the religious laws and even deny the divine revelations.
 Mosoa Kalamatal Imam Hussain (AS), Page 252, hadith 285.