The first king of Delhi Sultanate was Qutubuddin Aybak,slave of Muhammad of ghur.Later,Qutubuddin declared himself the sultan of Delhi and started as what we call Mamluk or slave dynasty.Arabic word mamluk means 'owned' and most remarkable is that the three rulers in mamluk dynasty- Qutubuddin, Iltutmish,and Balban were originally slaves.In those days, slave was valued like the the son of the king and so that slaves were made sultans. Qutubuddin Aibak managed to rule for only four years after he rose to power because he died while playing chaugan,a form of polo.Then came to the throne, Qutubuddin 's son-in-law,Sham-sud-din Iltutmish.

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Qutub-ud- din Aibak.