When word of the gathering army reached Medina, Muhammad and his senior leaders were confident in the fortifications of the city. His younger and more energetic members, however, wanted to march and fight the approaching Quraysh in the open. The glory of open battle won the debate.
The Muslim army from Medina numbered only 1000 when they went to Mount Uhud north of Medina (pictured), and was reduced further when 300 men returned to Medina, uncertain about the decision to fight in the open. Muhammad sent 50 archers to the slopes of Uhud to protect the flank of the majority, who were positioned in a valley. The battle took place on 19 March 625.
The initial success of the Muslims prompted the archers to leave their position to take part more directly against the Quraysh. This was against the orders of Muhammad, who had told them to stay on the slope (now called the Mount of the Archers). The Quraysh realized that they were no longer as vulnerable to arrows from above, and were able to send a group to outflank the archers.
Several Muslims were killed at the Battle of Uhud, and Muhammad was injured. The Muslims retreated up the slopes, and the Quraysh took this as a victory and returned to Mecca.
Six months later, the Quraysh decided again to take the offensive and occupy Medina, initiating The Battle of the Trench, a battle that turned out to not be a battle. I'll explain next time.