The Jews of Khaybar had enough military strength to face the Muslims unassisted by the Quraysh. The Prophet (may Allah bless him and grant him peace) wanted to reach an accord with the Jews of Khaybar as had been reached with the idolaters of Makkah, but the Jews were in no way prepared to extend friendship for peace. The Jews who had been banished from Madinah and had later settled in Khaybar were openly hostile to the Muslims. At the city of Khaybar, water was abundant and the land of Khaybar was among the richest soils of the Peninsula. Outside Khaybar, were volcanic planes untouched by greenery. Crossing such an area was extremely difficult.

In Arabic, Khaybar means "a fort". In this city there were present eight forts. In case of war, the people of Khaybar could arrange an army of twenty thousand. The city of Khaybar was very old. Till 530 AD, Arabian influence had been predominant here. The citizens of Khaybar reached an accord with Abu-Nawas in the year 530 AD. by which the Jewish influence began to surface. The Jews played a vital role in the development and settlement of the city and gradually became the majority. When the Prophet (may Allah bless him and grant him peace) decided to conquer Khaybar, there was not a single Arab in the City.

The Jews of Khaybar were also very rich. Their city was an important centre for trade. The jewellers of Khaybar were held in high esteem throughout Arabia. They would sell their jewels or rent them to the rich, with bonds of sureties. In Arabia, Jews had capitalised on this trade and though there were several other jewellers towards the north and south none of them could match their reputation. The area of Khaybar was very humid. Outsiders on reaching here were often hit by the "Sickness of water".

In fact this disease was Malaria and what the people of those times did not know was that the mosquito was the vector of this disease.

The Jews used to tell the naive Bedouins that in order to live in Khaybar unaffected by the disease, one must prostrate before entering the city and bray like a donkey. This procedure was called "Ta’shir".

In those times people used many methods to protect themselves from disease. They never drank stagnant water. If flowing water was not available, they used wine. They often used garlic that we know now to have anti-biotic properties. They used to live at high places believing the disease would not hit them there. They would leave Khaybar at the beginning of summer and return in autumn when there were fewer mosquitoes. They did these things even though they were not aware of the part the mosquito played in spreading disease.

When the Jews came to know of the ten-year truce, they were alarmed. Till then they had been comforted by their deal with the Makkans that had promised military help to each in case any one of them was attacked by the Muslims. After the Accord of Hudaybiyyah the agreement between the Jews and the Unbelievers automatically stood invalid. The Jews thus came to believe that confrontation with the Muslims had now become inevitable. They accumulated amenities of life in all eight of their forts, and their twenty thousand soldiers, armed to teeth, became ready to face fifteen hundred Muslims the Prophet (may Allah bless him and grant him peace) had set out with.

Meanwhile the Islamic army marched through the territories of Bani Ghatfan and Bani Farazha. Both these tribes were allies of Quraysh. When the Prophet (may Allah bless him and grant him peace) was moving towards Khaybar, these two tribes according to the law ought to have moved to help the Jews, but they were held in awe by the spirit of the Muslim army and they promised to stay neutral. They could compromise with the Muslims without hurting their alliance with the Quraysh. They also knew of the valour of the Muslim army from the battles of Badr, Uhud and Trench. It would not have been beneficial to strike against such brave men.

When the Islamic army reached Khaybar, the Prophet (may Allah bless him and grant him peace) addressed the Muslims: "We do not have necessary means to conquer these huge and strong forts. We have only swords, bows and arrows. With these weapons, the massive forts, built of stone, cannot be demolished, but we can compel the Jews to surrender. We can besiege them and throw dikes on canals passing through their forts. If the Jews have no water, they will soon be compelled to surrender".

The Muslims decided to attack each fort by turn. When the Muslims started to lay siege around Khaybar, they faced stones hurled by "Manjneeq" of the Jews. (Manjneeq means catapult in English). It was used to hurl heavy stones at the enemy).

The Jews of Khaybar had known the craft of carving balls out of stone and hurling them by catapults. They launched a massive bombardment of stones at the Muslims and it seemed the Muslims would not be able to face them. Here again, the Prophet’s (may Allah bless him and grant him peace) intelligent war-strategy worked. He ordered movable turrets to be built so the walls of the forts could be reached. These turrets would serve as armoured vehicles. By reaching the fort-walls, the Muslims would be safe. The catapults could only hit objects at some distance and could not injure the people standing directly under the straight walls. The people standing under the wall could face danger only from stones being thrown at them from the fort towers. These stones could only be thrown down from slits that had been made in the forts for this purpose. The remaining positions of the wall were safe for shelter.

Though the Prophet (may Allah bless him and grant him peace) had taken over the command of the army, the unhealthy atmosphere of Khaybar soon made him sick and he handed over the charge to Abu Bakr^R.A. Abu Bakr^R.A himself took to bed because of high fever after only 2 days of command. From him the command went to Umar^R.A bin Khatab. He also contracted fever as well and his health was badly impaired. He then sent for the leaders of the army from his bed and told them, "In my view no one is more suitable in this battle to take charge of the Islamic army than Ali^R.A. Ali^R.A is a stead-fast, brave and consistent person. He has so much valour that he would not turn his back even if he had to alone face a hundred soldiers. If there is anyone to conquer these forts, it is Ali^R.A. That is why I am handing over leadership of the army to him. To obey him is obligatory to you".

When Ali^R.A was given this charge, he had also contracted mild fever. On his first day of command, he put to siege the fort of "Natat". According to Baghwa Ibn-e-Abi-Alhadeed, a person wearing a steel helmet appeared at the wall of the fort of Natat and addressed the Muslims, "Who is your Commander?"

Ali^R.A replied, from the front of wall, "I am the Commander of the Muslim army. My name is Ali^R.A bin Abi Talib". That person called out, "O Ali, my name is Marhab. Out of these eight forts which you are seeing, one has been named after me. Have you the courage to face me?" Ali^R.A replied aloud, "I have never turned down any invitation to single combat, therefore I will not turn down your invitation".

Although Ali’s eyes were sore and his body bare of armour, he faced Marhab resolutely who was clad in strong armour and a steel helmet. There was a long and hard fight and at last Ali^R.A sent Marhab to death. After defeating Marhab, Ali^R.A ordered the door of Natat be broken by beams. On that day, the Muslims used three large tree trunks as beams each being carried by fifty men. While the Muslims were busy in breaking the door of the fort, Ali ordered some Muslims to climb up the walls of the fort by using a ladder. The Muslims first reached the walls of the fort and then through the ladder climbed into it. The Muslims also broke open the strong door of the fort and arrested the Jews who were inside. The Muslims were also able to recover large amounts of booty from the fort.

After conquering the fort of Natat, Ali^R.A decided to attack the fort of "Naem". During the battle of Khaybar, Ali^R.A was able to conquer four forts in ten days. The inhabitants of the remaining four forts surrendered to Ali^R.A without resistance.

The Prophet (may Allah bless him and grant him peace) had just recovered when he received the news of the fall of the first fort to the Muslims. In front of all the Muslims, the Prophet (may Allah bless him and grant him peace) embraced Ali^R.A and kissing his forehead said, "O Ali, you are Asad-Ullah, -- the Lion of Allah". This title of Ali^R.A is much remembered in Islamic tradition and is the one by which he was better known.

The Muslims received ample supplies of war-riches in this war.

After the victory of Khaybar, the Prophet (may Allah bless him and grant him peace) adopted great clemency towards the Jews. They were allowed to leave Khaybar if they willed and were also allowed to take with them whatever they liked, except dates, sheep and grain. Those Jews who did not want to leave Khaybar were permitted to stay and were given the concession to continue their previous trade. They were expected to pay a small tax called Jizyah to the Muslims in return for which the Muslims would provide them protection.

The Prophet (may Allah bless him and grant him peace) bestowed another favour upon the Jews by forbidding the Muslims to do "Mutah" with the Jewish women. Mutah was in fact temporary marriage with women of subdued nations, an Arabian tradition. This was later completely abolished by the Prophet (may Allah bless him and grant him peace) as the religion of Islam was progressively revealed and made known to the people. In addition, the commander of the Muslim army, Ali, also restricted the entrance of Muslim soldiers in Jewish orchards and oases so that their yield may not be damaged. The Prophet (may Allah bless him and grant him peace) married a Jewish woman "Safiyyah". Her first marriage had ended in divorce. She was then wedded to Kananah bin Abi Alhaqeeq. This person died in the Battle of Khaybar. She, after arrest had come to the share of Waheyah Kalbi. In lieu of her father’s status who was the chief of Khaybar, the Prophet (may Allah bless him and grant him peace) had paid for her freedom and wedded her. Safiyyah^R.A later on become a great source of knowledge and wisdom about Islam to Muslim women.

One day, a Muslim soldier, while passing through the forts of Khaybar was attacked and killed by an un-known assailant. Ali^R.A gathered the Jews and investigated the murder. The Jews swore that the murderer was not from the Jews of Khaybar and they were innocent. Ali^R.A presented the matter before the Prophet (may Allah bless him and grant him peace) and said that the Jewish heralds had absolved themselves from the murder. From whom was thus the blood-money to be sought?

The Prophet (may Allah bless him and grant him peace) said that as those people had sworn that the murderer of the Muslim soldier was not from the Jews, therefore he would accept their statement. He himself was ready to pay the blood-money for the deceased that he then did.

After the victory of Khaybar, the two Jewish tribes which lived in the area of the valley "Alqara" and two other tribes which dwelt at the places of "Fidk" and "Taimah" adopted a conciliatory attitude towards the Muslims and consented to give them "Jizyah".

While the Battle of Khaybar had been at its peak, two travellers arrived at Khaybar from Abyssinia. One of them was the Prophet’s (may Allah bless him and grant him peace) foster brother, Ja’far bin Abi Talib, the other Umroah bin Umayyah. Both of these had been among the first migrants to Abyssinia. After their return, none of the Arabs who had migrated, remained in Abyssinia.

The Jews of Khaybar were granted many concessions after the battle. They reopened their places of worship and indulged in prayers as usual. All of their sacred books and important documents that had come to the hands of the Muslims were also returned. Their relations with the Muslims became so good that a Jewish woman announced that she would send meat to the Prophet (may Allah bless him and grant him peace) cooked by her hands.

The name of this woman was Zaynab Bint Harth and she was the wife of Salaam bin Mashkam. She had a ram slaughtered as she had heard that the Prophet (may Allah bless him and grant him peace) was very fond of lamb’s leg. She then added poison to both legs, roasted them and sent the meal to the Prophet (may Allah bless him and grant him peace). When this roasted meat was presented to the Prophet (may Allah bless him and grant him peace), a Sahabi, named Bashir bin Bira bin Ma’roor, was in his company. It was the Prophet’s (may Allah bless him and grant him peace) habit: to share his meals with guests and the poor, the Prophet (may Allah bless him and grant him peace) presented one leg to him and from the other he himself tore a slice to eat.

Bashir bin Bira took a bite, chewed it and swallowed, but the Prophet (may Allah bless him and grant him peace) on chewing the first morsel spat it out. He told Bashir bin Bira urgently, "Do not eat this meat! It has been poisoned!" In bewilderment, Bashir threw away the leg, but the morsel of meat he had swallowed showed its effects and he soon died.

Zaynab bin Harth was arrested and questioned whether she had sent poisoned meat to the Prophet (may Allah bless him and grant him peace). She confessed saying, "I poisoned the meat with the view that the Prophet (may Allah bless him and grant him peace) would not eat this meat. If he was the true Messenger of Allah, he (may Allah bless him and grant him peace) would not be affected by the poison. As the Prophet (may Allah bless him and grant him peace) spat out the meat instantly, the truth of his Prophethood has been proved to me".

The famous works of Masoodi, Ibn-e-Hasham, Asad Baig, Tibri Ibu-Abi-Al-hadeed do not mention how the Muslims treated that woman.

Some Islamic scholars have written that the Prophet (may Allah bless him and grant him peace) before his death mentioned to his loved ones that the cause of his death was the same poison that had been given to him at Khaybar. We know that the Prophet (may Allah bless him and grant him peace) did not consume any of the poisoned meat but it has been conjectured that some fluid which would have oozed out of the meat by a little chewing could have been absorbed in his body, later becoming the cause of his illness and ultimately that of his death.