Imam Al-Hussayn (peace be upon him) said: "And I am not taking up arms in order to make merry, or be ecstatic over what I possess. I am not making mischief, nor exercising oppression. But, I am ready to fight for the sole goal of seeking reform of the Ummah of my grandfather, the Prophet of Allah (prayers and Allah's peace be upon him and his holy Household). I want to enjoin good and forbid evil and guide the affairs of the people as my grandfather, and my father, Ali bin Abi Taleb (peace be upon him) were doing." The revolution of Imam Al-Hussayn (peace be upon him) passed through many stages that set up the chapters of this timeless revolution, which remained and will remain shining to guide humanity, And among those stages when Imam (peace be upon him) left Mecca to Iraq to start the journey of divine love, as he earlier left the city of his grandfather to Mecca, and that was on the 8th of Dhu Al-Hijjah 60 AH, day of tarwiyah, after receiving many messages from people of Kufa, he (peace be upon him) sent an envoy to Kufa, and has chosen his cousin Muslim bin 'Aqeel (peace be upon him) for his goodness and eligibility for this task.
Since the arrival of Muslim to Kufa, he gathered the supporters and took the pledge of allegiance to Imam Al-Hussayn (peace be upon him) from the leaders of Kufa and its men, and then sent a letter to Imam Al-Hussayn (peace be upon him) urging him to go to Kufa, and once Imam Al-Hussayn (peace be upon him) received his letter he decided to go to Iraq.
Before departing, Imam Al-Hussayn (peace be upon him) stood up to deliver a sermon. He said: “All praise is due to Allah The Will of Allah be done. There is no might except in Allah Allah has blessed His Messenger. Death is inscribed on Adam's children like a necklace on a girl's neck. My passion to be reunited with my ancestors is like that of Jacob for Joseph, and the demise I shall soon meet is better for me. I see my limbs being torn by speeding steeds in the desert between al-Nawawis and Karbala’, so they shall fill, through my death, hollow bellies and starved pouches. There is no avoiding a day recorded by the Pen. Whatever pleases Allah also pleases us, we Ahl al-Bayt. We shall be patient as we face His trial, and He shall give us in full the rewards due to those who persevere. The Prophet's offspring shall not deviate from His path Rather, they shall be gathered before him in the presence of the most Holy One. His eyes shall be cooled upon seeing them assembled, and he shall fulfill his promise. Anyone among us who is ready to sacrifice himself and is determined to meet Allah should join our departing party, for I shall depart in the morning if Allah Almighty so wills”.
So, he (peace be upon him) left on Tuesday -day of tarwiyah- 8th of Dhu al-Hijjah, with eighty two men of his followers and his family before completion of pilgrimage, which means that the Imam (peace be upon him) did not complete his pilgrimage due to the seriousness of the situation as an Imam. Imam Al-Hussayn (peace be upon him) gathered his wives, children, sons, brothers, nephews and cousins and decided to get ou of Mecca.
Imam al-Hussayn (peace be upon him) was informed that Yazeed bin Mu'awiyah (curse be on them) has already send 'Amru Ibn Sa’eed Ibn Al-'As from Madinah to Mecca in great army to be the governor of the pilgrimage season, and has commanded him to arrest Al-Hussayn (peace be upon him) secretly and if not, he should assassinate him even if he's hang in the Kaa'ba's curtains. Imam Al-Hussayn (peace be upon him) decided to leave Mecca so that the sanctity and divine security of Mecca would not be compromised. Thus, the Imam (peace be upon him) changed his intention and rituals from Hajj to an individual Umrah. It is narrated that he said to his brother Mohammad Ibn Hanafiyah: "O brother, I fear than Yazeed Bin Mu'awyah assassinates me in the Kaa'ba, and I will be used to violate the sanctity of this House."