Israel from its birth was comprised of both Jews and Gentiles. God's covenant people were the Jews and Gentiles faithful and obedient to Him and His Covenant, within the nation.
Genesis 17:12
And he that is eight days old shall be circumcised among you, every man child in your generations, he that is born in the house, or bought with money of any stranger, which is not of thy seed.
Exodus 12:48
And when a stranger shall sojourn with thee, and will keep the passover to the Lord, let all his males be circumcised, and then let him come near and keep it; and he shall be as one that is born in the land: for no uncircumcised person shall eat thereof.
Exodus 12:49
One law shall be to him that is homeborn, and unto the stranger that sojourneth among you.
Leviticus 19:34
But the stranger that dwelleth with you shall be unto you as one born among you, and thou shalt love him as thyself; for ye were strangers in the land of Egypt: I am the Lord your God.
Leviticus 24:22
Ye shall have one manner of law, as well for the stranger, as for one of your own country: for I am the Lord your God.
Those faithful and obedient within the nation, God blessed.
Those unfaithful and disobedient, He slew. Ethnicity was and is irrelevant.
Numbers 25
9 And those that died in the plague were twenty and four thousand.
There has never been any substitute, ethnicity or otherwise, to this day, for faith and obedience.
