His instruction was now carried on totally by his father...
His instruction was now carried on totally by his father IMAM ALI IBN ABU TALIB (AS). In this atmosphere of learning, Imam HASAN (as) grew up to be a graceful and highly accomplished youth. After the Prophet's death, Imam Ali (as) led a secluded life for twenty-five years. During those years, he did not involve himself in political affairs except when expressly requested for consultation by the three caliphs.
On 'UTHMAN'S tragic death, the Muslim community of Medina repeatedly requested him to assume the caliphate. As soon as Imam Ali (as) became the caliph, a series of battles ensued: JAMAL, SIFFIN and NAHRAWAN. In all these battles, IMAM HASAN (AS) assisted his father with feats of valor of his own. CALIPHATE Imam Ali (as) was martyred on 21st of Ramadan, 40 A.H. (January 28, 661 A.D.). The Muslims then unanimously acknowledged IMAM HASAN (AS) as their caliph.
He had to shoulder such a great responsibility while still grieved by the loss of his revered father. When he addressed the nation from the pulpit for the first time, he described his qualities in detail, highlighting his indifference to property and wealth. He was quite emotional while saying that, so much so that tears choked his throat and his audience, too, burst into tears. Then he reminded people of his ancestors and their virtues.
ABDALLAH IBN ABBAS stood up and, after a short speech, invited people to take the oath of allegiance to Imam HASAN (AS). All obeyed willingly. IMAM HASAN (AS), before whose eyes the coming events were already their shadows, put to the eager audience the condition that they should follow him sincerely; that if he wanted to fight, they should all join him against the foe, and observe peace if he made a treaty.
All agreed to these terms; IMAM HASAN (AS) took up the administration, appointed governors and officials, and began to issue his verdicts in disputed matters. During that time, MU'AWIYA was firmly seated on his throne in Damascus, Syria. The battles he fought with IMAM ALI (AS) had been a profitable bargain for him through the cunning arbitration of AMR IBN AL-'AS. Northern Arabia and Iraq, which used to be ruled by Imam Ali (as), were now under the control of Imam HASAN (AS).
Soon disunity and dissension started prevailing due to the intrigues and plots of MU'AWIYA. Even Imam Ali's orders in the last year of his life were being ignored as is obvious from reviewing his sermons during that year.