THE Bradford Pals were formed from bands of friends or colleagues from all walks of life, who volunteered to serve their country shoulder-to-shoulder.
Tragically, this meant many were also destined to fall together on the battlefields in the unimaginable horror of trench warfare.
No-one knows for sure how many Bradford Pals were lost on July 1, as record-keeping in the chaos of battle was very difficult.
But after much research, the Bradford World War One Group believes 1,394 men went 'over the top' and 1,017 of these were either killed or injured.
Here, the group's secretary, Tricia Platts, explains how the volunteers were recruited and made the journey to the Somme:
"After August 4, 1914 towns and cities in England wanted to 'do their bit' in raising volunteers.
"In Bradford this was done through the Citizens' Army League which, with the approval of the War Office, set about raising a Bradford Battalion and for which the League would bear the cost of clothing, feeding and training the men.
"Sir WEB Priestley MP and a group of prominent Bradford businessmen established the Citizens' Army League in premises on Bridge Street on September 25, 1914 and invited the Lord Mayor to be their chairman.
"Rooms in the Bradford Mechanics' Institute were offered free of charge as the recruiting centre and the Bradford Daily Telegraph urged men to enlist: 'The special inducement of the new Bradford Service Battalion is that young men shall be enrolled to serve, shoulder to shoulder, with their friends and colleagues in civil life.'
"Within a month 1,069 men had enlisted and the first Battalion, Bradford Pals was born.
"Such was the number of volunteers, a second battalion was formed during the next few months and the long process of training these civilian volunteers could begin.
"The men were in camp at Skipton, then Ripon and then at Fovant in Wiltshire. Their first overseas posting was to Egypt where, for the first time, they encountered men of the British Indian Army: the Mysore Lancers were camped nearby and supplied the Bradford men with a very welcome alternative to the monotonous army rations in the form of bowls of curry, still very popular in Bradford today.
"The Bradford Territorials had already come across men from the Punjab fighting with the Lahore Division at Neuve Chapelle.
"Described in the Regimental History as 'tall men of fine physique who marched with wonderful spirit and élan', these men were much admired by the Bradford lads.
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"In February 1916 the Pals were shipped from Egypt to Marseille and then taken by train to northern France to prepare for what was intended to be 'the big break through'.
"We now know that July 1 was by no means a break through. The battle raged on until November by which time both sides were exhausted, severely depleted of men and resources, and virtually no further forward in terms of ground gained.
"We should however remember that this terrible Battle of the Somme also marked a turning point in the war.
"Many historians now agree that, although there were terrible battles to follow, the Somme marked the moment when the British Army was shown to be the match of anything the enemy could throw at it.
"However, families in Bradford now understood the full meaning of the recruiting slogan: 'Join Together; Serve Together' now also meant 'Die Together'."