Persians (pic. 4th from right) invaded India in 600 BC, then came Alexander (1st from left in 2nd row), Shack,Hun etc. to start Hindu Period.Hazrat Muhammad died in 632 AD. Within hundred years the Arabians became all powerful in Military strength and established a vast empire (pic. last row). Sultan Mahmood of Gazni invaded india in 1000 AD Muslim period extended upto entry of Birtish in 1857.