The Battle of the Trench (Ghazwa-e-Khandaq) – Islamic History in Simple English

 The Battle of the Trench (Khandaq) — Simple English 

After the defeat at Uhud, Abu Sufyan gathered a huge army from all over Arabia. The confederate force is estimated in the sources to have been about 10,000 men, prepared to attack Medina. This large army worried the Muslims because Medina’s population was much smaller. 

When the Prophet Muhammad (peace be upon him) learned of this, he called a meeting. Everyone knew a direct fight in the open was dangerous. In that meeting, Salman al-Farsi (Salman the Persian) advised digging a deep trench on the exposed side of Medina. He explained that Medina is protected on three sides by hills, so if the Muslims dug a trench on the only open side, the enemy cavalry could be blocked and the town would be better defended. The Prophet accepted Salman’s plan. 

The work began at once. The whole community took part: men, and others who could help. Sections of the trench were assigned to groups; the Prophet himself worked alongside the Companions. According to many accounts, in a short time the Muslims dug a trench roughly 5–6 km long along the exposed flank (sources give similar long measurements). This trench was wide and deep enough to stop cavalry. 

When the confederate armies, led by Abu Sufyan, arrived, they found the trench and could not cross it. The invaders camped and tried to find another way in. Meanwhile, the Muslims negotiated behind the scenes to break the alliance of some tribes. After about two weeks, due to the trench, poor weather and failing unity among the confederates, the invading force withdrew and returned to Mecca. The main military objective of taking Medina failed. 

During and after the siege, suspicion grew that the Jewish tribe Banu Qurayza had broken their treaty with the Muslims. The Banu Qurayza were then besieged and surrendered. A judgment was given by Sa‘d ibn Mu‘adh — who was asked to decide because of his status and ties to the tribe — and the accepted historical accounts record his ruling that the fighting men be punished in accordance with the laws of that time; the women and children were taken captive. This episode is recorded in classical sources and is debated by modern scholars. 

In short: the trench strategy saved Medina from being captured. The confederate coalition returned to Mecca without achieving its goals, and the episode changed the political balance in Arabia. The battle taught the Muslims crucial lessons about unity, defence, and the consequences of breaking treaties. 

Key historical points I checked (quick sources)

Confederate army size and Abu Sufyan’s leadership — Wikipedia / historical summaries. 

Salman al-Farsi’s advice to dig the trench and community digging — Islamic sources and summaries (IslamWeb, historiography). 

Trench approximate length (commonly reported ~5–6 km) — historical summaries and educational blogs. 

Siege and judgment of Banu Qurayza, decision by Sa‘d ibn Mu‘adh — classical sources and encyclopedia entries.