The Significance of the Hijri Calendar in Islam

The Hijri calendar holds great importance in the Muslim world, though many people may not be aware of it. It follows the lunar cycle and consists of 12 months, as clearly mentioned in the Qur’an in Surah At-Tawbah, Ayah 36:

إِنَّ عِدَّةَ ٱلشُّهُورِ عِندَ ٱللَّهِ ٱثْنَا عَشَرَ شَهْرًۭا فِى كِتَـٰبِ ٱللَّهِ يَوْمَ خَلَقَ ٱلسَّمَـٰوَٰتِ وَٱلْأَرْضَ مِنْهَآ أَرْبَعَةٌ حُرُمٌۭ ۚ ذَٰلِكَ ٱلدِّينُ ٱلْقَيِّمُ ۚ فَ”لَا تَظْلِمُوا۟ فِيهِنَّ أَنفُسَكُمْ ۚ وَقَـٰتِلُوا۟ ٱلْمُشْرِكِينَ كَآفَّةًۭ كَمَا يُقَـٰتِلُونَكُمْ كَآفَّةًۭ ۚ وَٱعْلَمُوٓا۟ أَنَّ ٱللَّهَ مَعَ ٱلْمُتَّقِينَ

“Indeed, the number of months ordained by Allah is twelve—in Allah’s Record since the day He created the heavens and the earth—of which four are sacred. That is the Right Way. So do not wrong one another during these months…”
— Qur’an 9:36, Dr. Mustafa Khattab (The Clear Quran)

During the time of the Quraysh tribe, people followed their own calendar and treated certain months as sacred, meaning no fighting was allowed. However, they manipulated the calendar by skipping or changing these sacred months so they could continue fighting. Allah revealed this verse to correct that practice and restore the proper understanding.

Why Was the Hijri Calendar Created?

Before the Hijri calendar, Muslims marked time using major events. For example, they might say, “He died two years after the Year of the Elephant.” This system became confusing, especially for official communication and sending letters to different regions.

Seventeen years after the Prophet’s migration (Hijrah), during the leadership of Khalifa Umar ibn al-Khattab, a complaint was made by Abu Musa al-Ash’ari, a governor in Basrah (Iraq). He noted that letters often arrived out of order because there was no consistent way to date them.

Khalifa Umar discussed the issue with his advisors. Some suggested starting the new calendar with the Prophet’s birth or death. However, most agreed that the most meaningful starting point was the Hijrah, the Prophet’s migration to Medina.

After consulting respected companions such as Uthman ibn Affan and Ali ibn Abi Talib, Khalifa Umar decided that the Hijri calendar would begin in the month of Muharram, with the year of the Prophet’s migration (622 AD) counted as Year 1.

Sources:
How and Why Did the Hijri Calendar Begin – AAU Blog
History of the Hijri Calendar – YouTube
Shia Scholar Explanation (YouTube, Shia Scholar, fact-checked from 5:44–9:19)
Friday Khutba at the Markham Islamic Institute – June 27, 2025 (Muharram 2, 1447 AH)

Disclaimer:
I am not a scholar. The material shared here is drawn from authentic sources and the teachings of qualified scholars. I do not offer personal interpretations, but aim only to summarize and present knowledge with care and respect. Allah knows best.