Waiting For Godot
In the play, "Waiting For Godot", Lucky is introduced as like the dog to Pozzo. Lucky is unique in a play where most of the characters talk incessantly: he only utters two sentences. Given Lucky's state of existence, his very name "Lucky" is ironic, especially since Vladimir observes that even "old dogs have more dignity."
Although, it doesn't clarify what race any of the other men are but by the way Pozzo treats him, he acts like he is his slave. Telling him to 'Sit!' or 'Back!', even 'Heel!'
The monologue is prompted by Pozzo when the tramps ask him to make Lucky "think". He asks them to give him his hat: when Lucky wears his hat, he is capable of thinking. The monologue is long, rambling words, and does not have any apparent end; it is only stopped when Vladimir takes the hat back. From what it seems like, it is referring to God.
Waiting For Godot - Lucky Speech
I would say because the way that Pozzo and Lucky dress, you can tell how wealthy or poor they are. Just by the time they were in, you can tell people were only focused on who they talked to in their social class. So Lucky and Pozzo were basically poor.
Waiting for Godot full play