With further reorganizations of the Ottoman Army, to include the creation of corps level headquarters, by 1911 the I Corps was headquartered in Harbiye. The Corps before the First Balkan War in 1911 was structured as such:
I Corps, Harbiye, Constantinople (Ferik Zeki Pasha)1st Infantry Division, Harbiye, Constantinople1st Infantry Regiment, Harbiye, Constantinople2nd Infantry Regiment, Bakırköy, Constantinople3rd Infantry Regiment, İşkodra1st Rifle Battalion, Taksim, Constantinople1st Field Artillery Regiment, Taksim, Constantinople1st Division Band, Harbiye, Constantinople2nd Infantry Division, Selimiye, Constantinople (Mirliva Prens Aziz Pasha)4th Infantry Regiment, İşkodra5th Infantry Regiment, Selimiye, Constantinople6th Infantry Regiment, Selimiye, Constantinople2nd Rifle Battalion, Selimiye, Constantinople2nd Field Artillery Regiment, Selimiye, Constantinople2nd Division Band, Selimiye, Constantinople3rd Infantry Division, Pangaltı, Constantinople (Mirliva Osman Pasha)7th Infantry Regiment, Taşkışla, Constantinople8th Infantry Regiment, Taşkışla, Constantinople9th Infantry Regiment, Kağıthane, Constantinople3rd Rifle Battalion, Tophane, Constantinople3rd Field Artillery Regiment, Rami Kışlası, Constantinople3rd Division Band, Taşkışla, ConstantinopleUnits of I Corps1st Rifle Regiment, Yıldız, Constantinople1st Cavalry Brigade, Davutpaşa, Constantinople1st Cavalry Regiment, Yıldız, Constantinople2nd Cavalry Regiment, Davutpaşa, Constantinople2nd Cavalry Brigade, Davutpaşa, Constantinople3rd Cavalry Regiment, Davutpaşa, Constantinople4th Cavalry Regiment, Selimiye, Constantinople1st Horse Artillery Battalion, Davutpaşa, Constantinople1st Mountain Artillery Battalion, Münzevî Kışlası, Constantinople1st Field Howitzer Battalion, Gümüşsuyu, Constantinople1st Engineer Battalion, İplikhane, Constantinople1st Telegraph Battalion, Ertuğrul Kışlası, Constantinople1st Medical Battalion, Ahırkapı, Constantinople1st Railroad Battalion, Ahırkapı, Constantinople2nd Railroad Battalion, Ahırkapı, ConstantinopleWar Academy, Harbiye, ConstantinopleCavalry Squadron, Harbiye, ConstantinopleInfantry Company, Harbiye, ConstantinopleProvisional Companies x 2, Harbiye, ConstantinopleMachine-gun Company, Harbiye, ConstantinopleBosporus Fortified Area Command, Bosporus, Constantinople1st Heavy Artillery Regiment, Bosporus, Constantinople2nd Heavy Artillery Regiment, Bosporus, ConstantinopleSearchlight Detachment, Bosporus, ConstantinopleTorpedo Detachment, Bosporus, ConstantinopleMine Detachment, Bosporus, ConstantinopleWireless Detachment, Bosporus, ConstantinopleOn October 17, 1912, the corps was structured as follows:
I Corps (Thrace, under the command of the Eastern Army)2nd Division, 3rd Division1st Provisional DivisionOn October 29, 1912, the corps was structured as follows:
I Corps (Thrace, under the command of the First Eastern Army)2nd Division, 3rd Division1st Provisional Division, Uşak Redif DivisionOn November 17, 1912, the corps was structured as follows:
I Corps (Thrace, under the command of the Chataldja Army)2nd Division, 3rd DivisionSouth Wing DetachmentI Provisional Reserve Corps29th DivisionErgli Redif Division, Kayseri Redif DivisionOn March 25, 1913, the corps was structured as follows:
I Corps (Thrace, under the command of the Chataldja Army)2nd DivisionFatih Redif DivisionI Provisional Reserve Corps29th Division,Ergli Redif Division, Kayseri Redif DivisionI Corps (Thrace)2nd Division, 28th Division, Fatih Infantry DivisionIn August 1914, November 1914, the corps was structured as follows:
I Corps (Thrace)1st Division, 2nd Division, 3rd DivisionIn Late April 1915, the corps was structured as follows:
I Corps (Thrace)1st Division, 2nd DivisionIn Late Summer 1915, January 1916, the corps was structured as follows:
I Corps (Gallipoli)2nd Division, 3rd DivisionIn August 1916, the corps was structured as follows:
I Corps (Gallipoli)14th Division, 16th DivisionIn December 1916, the corps was structured as follows:
I Corps (Thrace)14th Division, 16th DivisionIn August 1917, January 1918, June 1918, September 1918, the corps was structured as follows:
I Corps (Thrace)42nd DivisionIn November 1918, the corps was structured as follows:
I Corps (Thrace)55th DivisionIn January 1919, the corps was structured as follows:
I Corps (Thrace, Adrianople; present day Edirne)49th Division (Kırkkilise; present day Kırklareli)153rd Infantry Regiment, 154th Infantry Regiment, 155th Infantry Regiment, 185th Infantry Regiment60th Division (Malkara)186th Infantry Regiment, 187th Infantry Regiment