The First Army or First Guards Army of the Ottoman Empire (Turkish: Birinci Ordu or Hassa Ordusu) was one of the field armies of the Ottoman Army. It was formed in the middle 19th century during Ottoman military reforms. Formations Order of Battle, 1877 In 1877, it was stationed in Selimiye. It was composed of: Infantry: Seven line regiments and seven rifle battalion. 1st Regular Infantry Division (Birinci Nizamiye Fırkası) 2nd Regular Infantry Division (İkinci Nizamiye Fırkası) Cavalry: Five line regiments and one Cossack brigade. Cavalry Division (Süvari Fırkası) Artillery: Nine field and three horse batteries, one İhtiyat regiment. Artillery Division (Topçu Fırkası) Engineer: One sapper company, eight companies of engineers, one company of artificers. Engineer regiment (İstihkâm Alayı) x 2 Order of Battle, 1908 After the Young Turk Revolution and the establishment of the Second Constitutional Era on July 3, 1908, the new government initiated a major military reform. Army headquarters were modernized. Its operational area was Constantinople and the Bosporus, and it had units in Europe and Asia Minor. It commanded the following active divisions: The First Army also had inspectorate functions for four Redif (reserve) divisions: First Army Headquarters: 1st Infantry Division (Birinci Fırka) 2nd Infantry Division (İkinci Fırka) 1st Cavalry Division (Birinci Süvari Fırkası) 1st Artillery Division (Birinci Topçu Fırkası) Chataldja Fortified Area Command (Çatalca Müstahkem Mevkii Komutanlığı) Redif divisions of the First Army (name of the division denotes its location) 1st Bursa Reserve Infantry Division (Birinci Bursa Redif Fırkası) 2nd Kastamonu Reserve Infantry Division (İkinci Kastamonu Redif Fırkası) 3rd Ankara Reserve Infantry Division (Üçüncü Ankara Redif Fırkası) 4th Kayseri Reserve Infantry Division (Dördüncü Kayseri Redif Fırkası) Order of Battle, 1911 With further reorganizations of the Ottoman Army, to include the creation of corps level headquarters, by 1911 the Army was headquartered in Harbiye. The Army before the First Balkan War in 1911 was structured as such: Army Headquarters, Harbiye, Constantinople I Corps, Harbiye, Constantinople (Ferik Zeki Pasha) 1st Infantry Division, Harbiye, Constantinople (Colonel Hasan İzzet Bey) 2nd Infantry Division, Selimiye, Constantinople (Mirliva Prens Aziz Pasha) 3rd Infantry Division, Pangaltı, Constantinople (Mirliva Osman Pasha) War Academy, Harbiye, Constantinople Bosporus Fortified Area Command, Bosporus, Constantinople II Corps, Tekfur Dağı (Mirliva Şevket Turgut Pasha) 4th Infantry Division, Tekfur Dağı 5th Infantry Division, Gallipoli 6th Infantry Division, Izmir Dardanelles Fortified Area Command, Çanakkale III Corps, Kırk Kilise 7th Infantry Division, Kırk Kilise 8th Infantry Division, Çorlu 9th Infantry Division,