The Six Divisions of Cavalry (Altı Bölük) was a corps of mounted elite

Elite

Elite refers to an exceptional or privileged group that wields considerable power within its sphere of influence...

 soldiers in the Ottoman

Ottoman Empire

The Ottoman EmpireIt was usually referred to as the "Ottoman Empire", the "Turkish Empire", the "Ottoman Caliphate" or more commonly "Turkey" by its contemporaries...

 army. There were not really six but four division

Division (military)

A division is a large military unit or formation usually consisting of between 10,000 and 20,000 soldiers. In most armies, a division is composed of several regiments or brigades, and in turn several divisions typically make up a corps...

s. Two of the six were sub-divisions. The divisions were:

• Sipahis (From Persian, translated roughly as armymen)
• Silahdars (From Persian, translated roughly as weaponbearers)
• Ulufejis (translated as stipendiaries), organised in two sub-divisions:
  • Ulufejis of the Left
  • Ulufejis of the Right
• Gurebas (translated roughly as strangers), organised in two sub-divisions:
  • Gurebas of the Left
  • Gurebas of the Right

The elite cavalry was the mounted counterpart to the Janissaries

Janissary

The Janissaries were infantry units that formed the Ottoman sultan's household troops and bodyguards...

 and played an important part in the Ottoman army. The Six Divisions were probably founded during the reign of Sultan Mehmed II

Mehmed II

Mehmed II , was Sultan of the Ottoman Empire for a short time from 1444 to September 1446, and later from...

(1451-1481), but the Sipahis had existed since 1326.