A league is an old way to measure distance, and it was equal to about 3 miles. So half a league is roughly a mile and a half– the brigade/battalion was charging forward in the battlefield

The place where many soldiers would die in the battle (very scary & uncertain)

The exact number of soldiers was 600, riding horses

The captain commanded the soldiers to move forward bravely

Note: they are called "Light" to separate them from the "Heavy Brigade," another kind of cavalry unit at the time.Tennyson's poem is based on real events. In 1854, there was a Charge of the Light Brigade during the Crimean War.

The soldiers were ordered to attack.

The soldiers moved to the battlefield, prepared to fight and to die fighting.The brigade was ordered into the valley, even though they knew that they were going to die.

Emphasis on the small number of soldiers – few but brave soldiers riding on horseback