succession of nations

ثُمَّ جَعَلْنَـٰكُمْ خَلَـٰٓئِفَ فِى ٱلْأَرْضِ مِنۢ بَعْدِهِمْ لِنَنظُرَ كَيْفَ تَعْمَلُونَ

Then We made you successors in the land after them so that We may observe how you will do.