Hazrat Imam Hussain was born in 4 Hijri. He was the younger son of Hazrat Ali and Hazrat Fatima. His name, Hussain, was suggested by our holy prophet Muhammad (Peace be upon him). Once our holy prophet Muhammad (Peace be upon him) said,
"Hussain brlongs to me and I to him"
On another occasion, our holy prophet Muhammad (Peace be upon him) said,
"May Allah love him whi loves Hussain (R.A)".
He was very close to his grandfather i.e. Muhammad (Peace be upon him). Many times he used to sit on the back of our holy prophet Muhammad (Peace be upon him).
After his father's assassination, he was with his elder brother on the issue of the caliphate. It was very difficult for him to accept any other caliph except Hassan. And when Hazrat Muavia handed over the caliphate to his son Yazeed, it was Hazrat Imam Hussain who didn’t show his will to accept him as caliph. It was a great loss for Banu Ummaiyah as their caliphate could not be rectified without the pledge of Imam Hussain.
When he didn’t accept Yazeed as caliph, the people of Kufa wrote many letters to Imam Husain to rescue them from the forces of Yazeed who were harassing them. The friends and companions of Hazrat Imam Hussain asked him not to go there as they were aware of the nature of Kufi people. First Hazrat Imam sent his cousin Muslim bin Aqueel to see the situation. Muslim bin Aqueel was warmly welcomed there and wrote a letter to Hussain in which he discussed the situation of Kufa in detail. After his letter, Imam Hussain decided to go to Kufa but after sending this letter, Muslim bin Aqueel was martyred in Kufa.
When he was going to Kufa, he heard the news that Muslim bin Aqueel has been martyred. After hearing this news, many of his companions left him but he decided to proceed to Kufa. There were only 72 companions who decided to go with him.
At the point of Karbala, the forces of Yazeed siege him with his 72 companions. At this point, all the sources of food and water supply were cut down by the forces of Yazeed. All these actions aimed to get Imam Hussain's allegiance for Yazeed but all was of no use. These incidents happened in 61 Hijri. Imam Hussain refused to accept Yazeed as caliph then the army of Yazeed which were consisted of about 4000 people started a war against Imam Hussain and his companions.
All of his companions got martyred in this war. When only imam Hussain left behind, he visited his son Imam Zain ul Abideen and after handing over the Imamat (leadership) to him, returned to the battlefield. Hazrat Imam Hussain got martyred in this war on the 10th of the Muharram. His martyrdom is a symbol of ultimate bravery and till today, all the Muslims remember this incident with tremendous sorrow and pain in the deepest of their hearts.