Established by the Northern Command, September 1914, as part of K2. Early days were somewhat chaotic, the new volunteers having very few trained officers and NCOs to command them, no organised billets or equipment. In the early Summer of 1915, the Division was considered to be ready for France.

12-17 July 1915 : landed in France; the Division served with distinction on the Western Front for the remainder of the war, taking part in most of the significant actions.

The Divisions spent its initial period of trench familiarisation and then holding the front lines in the southern area of the Ypres salient.

Actions of the Bluff

The Battle of Albert (first phase of the Battle of the Somme 1916)

In the above action, the Division captured Fricourt, after suffering heavy losses.

The First Battle of the Scarpe (first phase of the Arras Offensive)

The Second Battle of the Scarpe (second phase of the Arras Offensive)

The Capture of Roeux (fourth phase of the Arras Offensive)

The First Battle of Passchendaele (seventh phase of the Third Battle of Ypres)

The Second Battle of Passchendaele (eighth phase of the Third Battle of Ypres)

The Battle of St Quentin (first phase of the First Battles of the Somme 1918)

The First Battle of Bapaume (second phase of the First Battles of the Somme 1918)

The Battle of Amiens

The Battle of Albert (first phase of the Second Battles of the Somme 1918)

The Battle of Bapaume (second phase of the Second Battles of the Somme 1918)

The Battle of Havrincourt (first phase of the Battles of the Hindenburg Line)

The Battle of Epehy (second phase of the Battles of the Hindenburg Line)

The Battle of Cambrai 1918 (sixth phase of the Battles of the Hindenburg Line)

The Pursuit to the Selle

The Battle of the Selle

The Battle of the Sambre

In total, the Division suffered more than 40,200 casualties during the Great War. Demobilisation was completed by May 1919.

50th Brigade

10th (Service) Bn, the West Yorkshires (joined September 1914)

7th (Service) Bn, the East Yorkshires (joined September 1914)

7th (Service) Bn, the Yorkshire (joined September 1914, disbanded February 1918)

6th (Service) Bn, the Dorsets (joined March 1915)

7th (Service) Bn, the York and Lancaster (joined August 1914, left March 1915)

50th Brigade Machine Gun Company (joined 12 February 1916, moved into 17 MG Bn 24 February 1918)

50th Trench Mortar Battery (joined 25 June 1916)

51st Brigade

7th (Service) Bn, the Lincolns (joined September 1914)

7th (Service) Bn, the Border (joined September 1914)

8th (Service) Bn, the South Staffordshire (joined September 1914, disbanded February 1918)

10th (Service) Bn, the Sherwood Foresters (joined September 1914)

3/4th Bn, the Royal West Kents (joined June 1917, left July 1917)

51st Brigade Machine Gun Company (joined 12 February 1916, moved into 17 MG Bn 24 February 1918)

51st Trench Mortar Battery (joined 3 July 1916)

52nd Brigade

9th (Service) Bn , the Northumberland Fusiliers (joined September 1914, left August 1917)

10th (Service) Bn , the Lancashire Fusiliers (joined September 1914)

9th (Service) Bn, the Duke of Wellington's (joined September 1914)

3/4th Bn, the Royal West Kents (joined August 1917, disbanded February 1917)

12th (Service) Bn, the Manchesters (joined September 1914)

52nd Brigade Machine Gun Company (joined 12 February 1916, moved into 17 MG Bn 24 February 1918)

52nd Trench Mortar Battery (joined 15 June 1916)

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Divisional Troops

6th (Service) Bn, the Dorsets (joined September 1914, left March 1915)

3/4th Bn, the Royal West Kents (joined July 1917, left August 1917)

7th (Service) Bn, the York and Lancaster (joined as Pioneers March 1915)

236th Machine Gun Company (joined 17 July 1917, moved into 17 MGBn 24 February 1918)

No 17 Machine Gun Battalion (created 24 February 1918)

No 12 Motor Machine Gun Battery (joined 10 July 1915, left 7 May 1916 when transferred to X Corps)

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Divisional Mounted Troops

A Squadron , the Yorkshire Dragoons (joined June 1915, left 10 May 1916)

17th Divisional Cyclist Company (formed 23 January 1915, left 24 May 1916)

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Divisional Artillery

LXXVIII Brigade, RFA

LXXIX Brigade, RFA

LXXX Brigade, RFA (broken up 31 August 1916)

LXXXI (H) Brigade, RFA (broken up 10-27 January 1917)

17th Heavy Battery, RGA (a Battery of 4 60-lbr guns raised with the Division but moved independently to France in October 1915, and joined XXIX Heavy Artillery Brigade RGA)

17th Divisional Ammunition Column

V.17 Heavy Trench Mortar Battery RFA (joined in 22 August 1916, transferred to V Corps 28 February 1918)

X.17, Y.17 and Z.17 Medium Mortar Batteries RFA (joined by 22 August 1916; by 28 February 1918, Z broken up and batteries reorganised to have 6 x 6-inch weapons each)

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Engineer Units

77th Field Company (joined Sep 1914)

78th Field Company (joined Sep 1914)

93rd Field Company (joined Jan 1915)

17th Divisional Signal Company (joined Sep 1914)

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Field Ambulances

51st Field Ambulance (joined Jul 1914)

52nd Field Ambulance (joined Jul 1914)

53rd Field Ambulance (joined Jul 1914)

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17th Divisional Train ASC (146, 147, 148 and 149 Coys ASC)

17th Divisional MT Supply Column ASC (257 Coy ASC)

218th Divisional Employment Company (joined 9 June 1917)

29th Mobile Veterinary Section

34th Sanitary Section ( left 10 March 1917, for XIII Corps)

17th Divisional Motor Ambulance Workshop (on 2 April 1916, absorbed by Divisional Train)