The Hijra (هِجْرَة), or withdrawal, is the emigration of Muhammad and his followers to the city of Medina in 622, and marks the start of the Hijri year of the Islamic calendar. The current Islamic Year is 1429 AH.pilgrimage, Hijra means something like a journey. It generally conotes a migration, specifically the migration of Muhammad from Mecca to Medina.
The actual event of migration started in Thursday 26 in the Month of Safar AH 1 (9 September 622) of that year.
That year was named The permission to travel. 17 years later, that year was chosen as the year to start counting from: first year of Hijra, 1 After Hijra or 1 AH. The first day of 1 AH, corresponds to Friday July 16th, 622 CE in the Julian Calendar.
The Muslim dates are in the Islamic calendar extended back in time. The Western dates are in the Julian calendar. The Hijra is celebrated annually on 8 Rabi' I, about 66 days after 1 Muharram, the first day of the Muslim year. Many writers confuse the first day of the year of the Hijra with the date of the Migration to Medina itself, erroneously stating that the Hijra occurred on 1 Muharram AH 1 or 16 July 622.
All dates given above may have occurred about 89 days (three lunar months) earlier in the Julian calendar. The calendar conversions quoted above may not have been corrected by early Muslims for the intercalary months (probably three) which had been inserted in the lunar calendar between the year of the Hijra and the year of Muhammad's last Hajj (AH 10), when intercalary months were forbidden.
Muhammad's preachings did not at first have much success in the city of Mecca. His tribe, the Quraysh, which was in charge of the Kaaba, persecuted and harassed him continuously. This eventually led to the Migration to Medina.
According to Sunni sources:
bgcolor=#F0FFF0|some time in 638 AD, Abu Musa Asha'ari, the Governor of Basra wrote:
"Amir-ul-Mominin, we receive instructions from you every now and then, but as the letters are undated, and some times the contents of the letters differ, it becomes difficult to ascertain as to which instructions are to be followed."
That set Umar thinking. In the meantime, he received from Yemen a draft for some money which was encashable in Shaban. Umar thought that the practice of merely mentioning the month in such cases was defective for one could not be sure whether the month referred to was of the current or the following year.
Umar convened an assembly to consider the question of calendar reform.
Some one suggested that the Roman calendar should be adopted. After discussion the proposal was rejected as the Roman calendar dated from too remote an era and was cumbersome.
It was next considered whether the Persian calendar might be adopted. Hormuzan explained the salient features of the Persian calendar called 'Mahroz'. The consensus of opinion was that such a calendar would not be suitable for the Muslims.
The general opinion was that instead of adopting any alien calendar, the Muslims should have a calendar of their own. This was agreed to, and the point next considered was from when should such an era begin?
Some one suggested that the era should begin from the date of birth of the Holy Prophet. Some suggested that it should begin from the death of the Holy Prophet. Ali suggested that it should begin from the date the Muslims migrated from Mecca to Madina. After discussion, Ali's suggestion was agreed to.
The Holy Prophet had migrated in the month of Rabi-ulAwwal, when the year had already run two months and eight days. Next the question arose from which month should the new era start.
Some one suggested that the calendar should start with the month of Rajab as in the pre-Islamic period this month was held sacred. Some one proposed that the first month should be Ramzan as that is a sacred month for the Muslims. Another proposal was that the first month should be 'Zul Hajj' as that is the month of the pilgrimage.
Usman suggested that as in Arabia the year started with Muharram the new era should also start with Muharram. This suggestion was accepted. The date was accordingly pushed back by two months and eight days, and the new Hijri calendar began with the first day of Muharram in the year of migration rather than from the actual date of migration.
Umar accordingly issued instructions to all concerned regarding the enforcement of the Hijri calendar
Hakim Muhammad Said wrote:
bgcolor=#F0FFF0|The Hijra took place on Tuesday, Rabi 1, 8th. The first of that year -that is, al-Muharram-fell on a Thursday according to the average (calculation).
After this had become generally known, it was considered (the correct date). However, according to observation (of the new moon) and astronomical(?) calculation, the day fell on a Friday. The author of the Nihayat al-idrak said that (the Hijra) was used, and for all future times the era was counted from it. Agreement on this matter was reached in the year 17 of the Hijra, the fourth year of the caliphate of 'Umar. Until then, each year (after the Hijra) was called after its main event, and this was used for dating purposes. The first year of the Prophet's residence in Medina was thus called: 'The permission to travel'. The second year was called: 'The year of the command to fight'. The third year: 'The year of the test', and so on. Afterwards, the custom of naming the year after the main events was abandoned.