I, Moroni, am going to tell you about the ancient inhabitants of the "north country" who were killed by God. 
My source is the set of 24 plates which were found by the people of Limhi, which is called the Book of Ether. 
3 And as I suppose that the first part of this record, which speaks concerning the creation of the world, and also of Adam, and an account from that time even to the great tower, and whatsoever things transpired among the children of men until that time, is had among the Jews --
The first part is about the creation of the world, and the story from Adam to the Tower of Babel.
4Therefore I do not write those things which transpired from the days of Adam until that time; but they are had upon the plates; and whoso findeth them, the same will have power that he may get the full account.
The Jews have that part, so I'm going to skip it. 
I'll tell the story from the Tower of Babel until they were destroyed. 
The author of the 24 plates is Ether, and this is his genealogy. 
Coriantor was the son of Moron. 
33 Which Jared came forth with his brother and their families, with some others and their families, from the great tower, at the time the Lord confounded the language of the people, and swore in his wrath that they should be scattered upon all the face of the earth; and according to the word of the Lord the people were scattered.
The Jaredites were Israelites who lived at the time of the Tower of Babel. 
34 And the brother of Jared being a large and mighty man, and a man highly favored of the Lord, Jared, his brother, said unto him: Cry unto the Lord, that he will not confound us that we may not understand our words.
35 And it came to pass that the brother of Jared did cry unto the Lord, and the Lord had compassion upon Jared; therefore he did not confound the language of Jared; and Jared and his brother were not confounded.
The brother of Jared  was a large, mighty (but apparently nameless) man who was "highly favored of the Lord."
Jared said to his brother,
Cry to the Lord so that he won't confound our language so we can still understand each other.
So the brother of Jared cried to the Lord, and the Lord didn't confound the language between them.
Then Jared said to his brother,
Cry again to the Lord, and ask him not to confound the language of our friends.
So the brother of Jared cried to the Lord, and the Lord didn't confound the language of their friends amd families.
38 And it came to pass that Jared spake again unto his brother, saying: Go and inquire of the Lord whether he will drive us out of the land, and if he will drive us out of the land, cry unto him whither we shall go. And who knoweth but the Lord will carry us forth into a land which is choice above all the earth? And if it so be, let us be faithful unto the Lord, that we may receive it for our inheritance.
Jared asked his brother to ask God what God will do with them. "Who knows?," Jared said, "maybe God will carry us to a land that better than any other land in the whole world."
So Jared's brother cried to the Lord,
and the Lord heard him, and said to him,
41 Go to and gather together thy flocks, both male and female, of every kind; and also of the seed of the earth of every kind; and thy families; and also Jared thy brother and his family; and also thy friends and their families, and the friends of Jared and their families.
42 And when thou hast done this thou shalt go at the head of them down into the valley which is northward. And there will I meet thee, and I will go before thee into a land which is choice above all the lands of the earth.
43 And there will I bless thee and thy seed, and raise up unto me of thy seed, and of the seed of thy brother, and they who shall go with thee, a great nation. And there shall be none greater than the nation which I will raise up unto me of thy seed, upon all the face of the earth. And thus I will do unto thee because this long time ye have cried unto me.
Go get a male and female from each of your flocks and every kind of plant seed that exists on earth.
Then gather all your friends and families, and meet me in the valley to the north.
I'll lead you to a land that is better than any other land on earth.
I'll bless you and your seed and your brother's seed and make a great nation out of all that seed, the greatest nation on earth.
I'll raise your seed up to me on the face of the earth.
I'm doing all this because you cried to me for a long time.