1908
 9th Battalion, The Duke of Cambridge's Own (Middlesex Regiment) 
 
Boer War 
 South Africa 1900-02 
 
 The Great War 
Four Battalions formed
 
 1914 
1st / 9th Battalion 2nd / 9th Battalion
 
 1915 
3rd / 9th Battalion 4th / 9th Battalion
 
 1916 
3rd / 9th Battalion re-designated as 9th (Reserve) Battalion
 
 
7th (Reserve) Battalion absorbed 8th , 9th , 10th (Reserve) Battalions
 
 1917 
2nd / 9th Battalion disbanded
 
 1919 
1st / 9th Battalion disembodied
 
 1917 
Location of operations
 
 
Battle Honours awarded to The Middlesex Regiment (Duke of Cambridge's Own)
 
 
attributable to 1st / 9th Battalion:
 
 
 9th Battalion, The Duke of Cambridge's Own (Middlesex Regiment) 
 
 
 9th Battalion, The Middlesex Regiment (Duke of Cambridge's Own) 
 
 1938 
Change of arm and re-designated as:
 
 
 60th Searchlight Regiment, Royal Engineers ( 9th Battalion, The Middlesex Regiment 
 
 
 (Duke of Cambridge's Own)) 
 
 1940 
Change of arm and re-designated as:
 
 
 60th Searchlight Regiment, Royal Artillery ( 9th Battalion, The Middlesex Regiment (Duke 
 
 
 126th Light Anti-Aircraft Regiment, Royal Artillery ( 9th Battalion, The Middlesex 
 
 
 Regiment (Duke of Cambridge's Own)) 
 
 1944 
Deployed to North West Europe as a Mobile Light Anti-Aircraft Regiment
 
 
 595th Light Anti-Aircraft Regiment, Royal Artillery, ( 9th Battalion, The Middlesex 
 
 
 Regiment (The Duke of Cambridge's Own)) 
 
 
 595th Light Anti-Aircraft and Searchlight Regiment, Royal Artillery ( 9th Battalion, The Middlesex Regiment (The Duke of Cambridge's Own)) 
 
 
571st Light Anti-Aircraft Regiment, Royal Artillery
 
 
604th (Mixed) Light Anti-Aircraft and Searchlight Regiment, Royal Artillery
 
 
[formerly: 604th Searchlight Regiment, Royal Artillery (Royal Fusiliers)
 
 
69th Searchlight Regiment, Royal Artillery ( 3rd City of London)
 
 
10th ( 3rd City of London) Battalion, Royal Fusiliers (City of London Regiment)
 
 
3rd (City of London) Battalion, The London Regiment (Royal Fusiliers)]
 
 
 571st Light Anti-Aircraft Regiment, Royal Artillery, ( 9th Battalion, The Middlesex 
 
 
7th Battalion and 8th Battalion
 
 
[formerly: 11th Battalion ( 8th Middlesex) The Parachute Regiment]
 
 
 5th Battalion, The Middlesex Regiment (Duke of Cambridge's Own) 
 
 
 D Company (Middlesex), 5th (Volunteer) Battalion, The Queen's Regiment 
 
 
 A and B Companies, 10th (Territorial) Battalion, The Queen's Regiment (Middlesex) 
 
 1969 
10th (Territorial) Battalion, The Queen's Regiment (Middlesex) reduced to Cadre role, Home Defence
 
 1971 
5
th (Volunteer) Battalion, The Queen's Regiment Amalgamated with: 6
th (Territorial) Battalion, The Queen's Regiment (Queen's Surrey) 10
th (Territorial) Battalion, The Queen's Regiment (Middlesex) The Greater London Regiment, Royal Artillery (Territorials) The Surrey Yeomanry (Queen Mary's Regiment), Royal Artillery Territorials [formerly: 3
rd , 6
th , 11
th , 17
th , 19
th , 22
nd and 23
rd Battalions, The London Regiment 3
rd Battalion, The London Scottish ( 97
th Anti-Aircraft Regiment) 4
th and 5
th Battalions, The Queen's Royal Regiment (West Surrey) 5
th and 6
th Battalions, The East Surrey Regiment 5
th , 6
th and 7
th Battalions, The Essex Regiment 7
th , 8
th and 9
th Battalions, The Middlesex Regiment (Duke of Cambridge's Own) 1
st , 4
th , 6
th and 7
th London Brigades, Royal Field Artillery 2
nd London Divisional Royal Engineers The Surrey Yeomanry (Queen Mary's Regiment)]
To become:
 6th (Volunteer) Battalion, The Queen's Regiment 
 
1975 
Amalgamated with:
7th (Volunteer) Battalion, The Queen's Regiment [formerly: 4th and 5th Battalions, The Buffs (Royal East Kent Regiment) 4th and 5th Battalions, The Queen's Own Royal West Kent Regiment 4th and 5th Battalions, The Royal Sussex Regiment part of The Kent and County of London Yeomanry (Sharpshooters)]
To become:
 6th / 7th (Volunteer) Battalion, The Queen's Regiment 
 
1986 
B and D Companies, 6
th / 7
th (Volunteer) Battalion, The Queen's Regiment formed: 
 A and B Companies, 8th (Volunteer) Battalion, The Queen's Fusiliers (City of London) 
with: C (City of London) Company, coming from 5th (Volunteer) Battalion, The Royal Regiment of Fusiliers
 
 1993 
A Company, 8
th (Volunteer) Battalion, The Queen's Fusiliers (City of London) reverted to: 6
th / 7
th Battalion, The Princess of Wales's Royal Regiment (Queen's and Royal Hampshires)
[formerly: 6th / 7th (Volunteer) Battalion, The Queen's Regiment] B and C Companies, 8th (Volunteer) Battalion, The Queen's Fusiliers (City of London) joined with: G (London Scottish) Company, 1st Battalion, The 51st Highland Volunteers D (London Irish Rifles) Company, 4th (Volunteer) Battalion, The Royal Irish Rangers To form:
 The London Regiment 
organised as: A (London Scottish) Company B (Queen's Regiment) Company C (City of London Fusiliers) Company D (London Irish Rifles) Company HQ (Anzio) Company
 
 1999 
Under the Strategic Defence Review of November 1998  The London Regiment absorbed two companies from 4th Battalion, The Royal Green Jackets to be re-organised as: HQ (Anzio) Company A (London Scottish) Company B (Queen's Regiment) Company C (City of London Fusiliers) Company D (London Irish Rifles) Company F (Royal Green Jackets) Company G (Royal Green Jackets) Company
 
 2007 
F and G (Royal Green Jackets) Companies moved to join: 7
th Battalion, The Rifles leaving HQ and four companies with:
 The London Regiment 
 
2017
B (Queen’s Regiment) Company transferred to the 4th Battalion the Princess of Wales’s Royal Regiment with loss of  title.