The Men of Dale
 

I was wondering if anyone knows who the people who lived in Dale were related to. Like the Rohrrim were related to the Edain.

Funny you should mention them but the Dalemen were related to the Rohirrim.

And the Beornings...

well the Rohirrim did originally live up north, around where the men of Dale lived, when Gondor called for their aid and gave them land, a majority moved south and lived what is now called Rohan. read the appendices on Eorl the Young, there is more info on it there.

According to a reference book of mine, the people of Dale traced themselves back to the Edain. They along with others who did not go to Numenor were called "Men of the Twilight" or "Middle Peoples". Others in this group were the Rohirrim, Northmen, Beornings, Woodmen, and others living in the Vales of Anduin.

Re:
 

Yes, the Edain were the first of men, folks like Barahir, Beren, and that bunch of fellows who got involved with the wars between the Elves and Morgoth.

The Dale-men (and surrounding areas like Laketown), and the Rohirrim were descended from a long line from those original men, but none were more closely descended than the Beornings.

Likewise, I think the Dunlanders were descended, perhaps from the traitors, the dark Edain who stabbed the Eldar and the Edain in the back, the 'original easterlings' (who weren't really from that far east). After the remnants fled (if any did ... I can't really remember) from the lost battle, they may have settled in the lands west of the Gap of Rohan.

As for the folks of Bree, while they may have been related to the Dunlanders, they never left Bree, never were involved in any treachery or anything, and never fell into shadows, so to speak. They're just, Bree-folk. They always have been.

The Edain, the special ones who helped elves out, obviously were taken to Numenor and became the Dunedain.

keep in mind that the men weren't classified as evil and good, there were those that didn't travel to Beleriand, they could've just stayed in ME and fell under the influences when Beleriand sank...