The Life of the Prophet Muhammad (pbuh)
Battle of Khandaq / Ahzab (5 AH)
Overview
Battle of Khandaq (Trench) / Battle of Ahzab (Confederates) — a siege battle in which the Muslims used an innovative defensive strategy to repel a massive coalition army.
| Date | Shawwal–Dhul Qa'dah, 5 AH (February–March 627 CE) |
| Location | North side of Madinah |
| Muslim force | ~3,000 men |
| Coalition (Ahzab) force | ~10,000 — Quraysh + Banu Nadir + Ghatafan + other tribes |
| Duration | ~15–27 days (siege, not open battle) |
| Outcome | Muslim victory; coalition withdrew without breakthrough |
Background and causes
The Banu Nadir, a Jewish tribe previously expelled from Madinah for treaty violations, travelled to Makkah and other tribes to organise a massive coalition (the Ahzab — "Confederates") with the sole aim of destroying the Muslim community once and for all. This was the largest threat Madinah had ever faced.
Salman al-Farsi's plan — the trench
Salman al-Farsi (RA), a Persian Companion, advised digging a deep trench (khandaq) along the open northern approach to Madinah — the only side not naturally protected by mountains or buildings. This defensive tactic was unknown to the Arabs, who were accustomed to open field battles.
- The trench was approximately 5.5 km long, 4–9 m wide, and 3 m deep.
- All 3,000 Muslims — including the Prophet ﷺ himself — participated in the digging.
- It was completed in approximately 6 days of intensive work.
Key events of the siege
- The trench held: The coalition cavalry repeatedly tried to cross but could not. This was completely unexpected — Arab horses could not jump the trench under fire.
- Amr ibn Abd Wudd — a legendary Quraysh warrior — managed to cross a narrow section with a small group. Ali ibn Abi Talib (RA) challenged and killed him in single combat, ending the only serious breach attempt.
- Banu Qurayza breach treaty: This Jewish tribe within Madinah secretly agreed to assist the coalition — creating the alarming prospect of attack from inside and outside simultaneously. The Prophet ﷺ sent negotiators, and the situation was tense but did not fully materialise.
- Nuaym ibn Masud's mission: This man secretly converted to Islam and, with the Prophet's ﷺ permission, spread distrust between the Quraysh, Banu Nadir and Banu Qurayza by carrying contradictory messages to each. This shattered the coalition's unity.
- Divine aid — wind and cold: Allah sent a fierce, bitterly cold wind that overturned the coalition's cooking pots and tents (Surah Al-Ahzab 33:9). Demoralised and unable to coordinate, Abu Sufyan ordered a withdrawal.
Outcome and aftermath
- The coalition withdrew without having crossed the trench; Madinah was never breached.
- No significant open battle took place — the victory was strategic and psychological.
- After the siege, the Prophet ﷺ dealt with Banu Qurayza for their treaty violation.
- Quraysh power broken: They would never again mount a unified offensive against Madinah.
Surah Al-Ahzab (33:9)
"O you who have believed, remember the favour of Allah upon you when armies came to [attack] you and We sent upon them a wind and armies [of angels] you did not see."
This verse confirms divine intervention as the ultimate cause of the Muslim victory.
"O you who have believed, remember the favour of Allah upon you when armies came to [attack] you and We sent upon them a wind and armies [of angels] you did not see."
This verse confirms divine intervention as the ultimate cause of the Muslim victory.
Significance
- Strategic genius: The trench strategy demonstrated that wisdom and innovation can overcome physical disadvantage — a key Islamic principle.
- Unity of the Ummah: The entire community — regardless of rank — worked side by side, including the Prophet ﷺ. This demonstrated Islamic equality and solidarity.
- Last Quraysh offensive: The Prophet ﷺ reportedly said after Khandaq: "From now on, we will attack them; they will not attack us." The initiative had shifted to the Muslims.
- Path to the Treaty of Hudaybiyyah and Conquest of Makkah: Khandaq's outcome paved the way for the Muslims' eventual return to Makkah.
The examiner often asks: "How important was Salman al-Farsi's contribution?" The answer must credit his specific idea (trench), explain why it worked (unknown to Arabs, cavalry could not cross), and then assess: was it the most important factor, or was divine intervention (the wind) more decisive? Argue your position with evidence.