By Alastair Lawson
As the 90th anniversary of the Battle of the Somme is commemorated, the Indian army also has good reason for remembrance.
The Indian cavalry suffered because of poor communications
Two Indian regiments took part in the first and only cavalry charge of the battle - between the High Wood and Delville Wood area - but were forced to retreat under heavy fire.
Like other advances in the battle, the joint Indian and British assault fell victim to poor communications.
By the time orders came through for them to go forward, the Germans had been able to strengthen their positions and the Indian horsemen and their British counterparts were unable to make progress because of small arms and shrapnel fire.
"This probably reinforced the increasing realisation among British generals that cavalry charges using horses were a thing of the past," says Imperial War Museum historian Nigel Steel.
"The cavalry was only supposed to be deployed after the terrain had been cleared by the infantry. It was not envisaged that they should suffer anything like the same casualty levels as their infantry counterparts."
The Somme was more a battle fought by the infantry
The cavalry charge on 14 July was conducted by two regiments, the 20th Deccan Horse and the British Seventh Dragoon Guards, who were supported by another Indian regiment, the 34th Poona Horse.
They were ordered to provide back-up to an infantry advance beyond High Wood, near the Carnoy Valley area of the Somme battleground.
The Indians and British suffered 102 casualties and lost about 130 horses.
"Although the cavalry regiments were eager to take part in the Somme once hostilities commenced, it was primarily a battle fought between infantry and artillery regiments," Mr Steel said.
"The terrain and nature of the battle were not really suitable for cavalry charges which is why they had to wait for around a fortnight before they saw action.
"Because lines of communications during the battle were often extremely stretched, it took a long time before their orders finally came through and time for them to get into position.
"British troops had captured a large amount of ground and the idea was that the cavalry would exploit those gains. Because their orders came through so late it was almost after the moment, and the Germans were able to re-group," he said.
"Had they been able to push forward first thing in the morning, their advance I believe would have been more successful."
The Indian cavalry was called to the front line again on 15 September, but tanks which were supposed to punch holes for them to advance through enemy lines failed to clear the ground satisfactorily.
"Apart from those two episodes, Indian soldiers in the Somme were kept behind the lines. There was so little for them to do, in fact, that many of the cavalry soldiers joined working parties which provided important medical and food supplies to troops serving on the front," Mr Steel said.
But if the Indian army did not see much action in the Somme, it nevertheless fought in almost every other major theatre of operations during World War I.
In 1914, there were 161,000 troops on the Western Front, providing a valuable source of trained men.
Thousands of Indian troops died in World War I
They were soon involved in fierce fighting around Ypres and losses were heavy.
The average Indian battalion had 764 men when it landed; by early November the 47th Sikhs had only 385 men fit for duty.
The fighting came as a shock to soldiers more used to colonial warfare. One man wrote home: "This is not war; it is the ending of the world."
The troops were taken out of the line and rested in early 1915, but were soon back in the trenches and involved in the heaviest fighting.
The Indian Corps provided half the attacking force at the Battle of Neuve Chapelle in March, and the Lahore Division was thrown into the counter-attack at the Second Battle of Ypres in April.
The Indians again took heavy losses at the Battle of Loos in September.
But towards the end of the war, the generals decided it made strategic sense to concentrate the Indian army in the Middle East, where it was easier to send reinforcements and supplies from India.
Two Indian cavalry divisions remained on the Western Front until March 1918, when they were transferred to Palestine to take part in the offensive against the Turks.