The first British troops arrived in Northern France on 12 August 1914 to support the French and Belgian armies. They were met by a much larger and much better prepared German Army. Between October and December 1914, the British and its allies suffered defeat after defeat and were forced to retreat.

By the end of the year, almost all of the British Expeditionary Force had been killed or wounded. If it had not been for the arrival and bravery of the Indian reinforcements, the war could have been lost then. The Indians arrived on 26 September 1914 and included three Sikh battalions. The lines held and the retreat was halted. The Indian soldiers took part in their first major engagement at the Battle of Ypres.

The Mons Star medal was named after the Belgian town of Mons where the British took part in their first major battle of the war. The following months as the Allies were forced to retreat are known as the Retreat from Mons. The Mons Star was awarded to those soldiers of the British Expeditionary Force and the Indian Expeditionary Force who fought between 5 August and 23 November 1914.