Simplify the following text for a Grade 13 native English-speaking person.
Original: By the mid-2nd millennium BC offshoots of the Proto-Indo-Europeans had reached Western Europe , Anatolia , the Aegean , Iranian plateau and later reach northern India .
Simplified: By the mid-2nd millennium BC offshoots of the Proto-Indo-Europeans had reached Anatolia , the Aegean , Northern India , and likely Western Europe .