Original: Some of the largest groups were the  'Aryans', Greeks, Scythians, Persians, White Huns, Arabs, Turks, Mongols and other Eurasian groups right up until the British who left in the late 1940s.
Simplified: The region of Pakistan has been invaded in the past, occupied and settled by many different people, including Aryans, Greeks, White Huns, Arabs, Turks, Mongols and various Eurasian groups.