Should I place a comma between the two dependent clauses?

Question

Here are the two examples; please tell me if I should place a comma between the two dependent clauses that come before the main clause. I'd also like an explanation, please.

Example# 1:

(with a comma)

Published in 1960, and narrated by a young girl in the 1930s, To Kill a Mockingbird recounts the coming-of-age of Scout Finch in the fictional Maycomb, Alabama.

or

(without a comma)

Published in 1960 and narrated by a young girl in the 1930s, To Kill a Mockingbird recounts the coming-of-age of Scout Finch in the fictional Maycomb, Alabama.

Example # 2

(with a comma)

Given the context and history in which Tom comes of age, and given that he had already participated in a trial and had been found guilty, Tom knows that his request for an appeal will be denied.

or

(without a comma)

Given the context and history in which Tom comes of age and given that he had already participated in a trial and had been found guilty, Tom knows that his request for an appeal will be denied.

Answer 1

These are not dependent clauses: they are participle phrases, the same as

Tired, he decided to sit down.

Note that the participle phrase is separated from the rest of the sentence by a single comma.

What makes your first sentence complicated is that there are two participle phrases. This can be handled in two ways:

Tired, confused, he decided to sit down
Tired and confused, he decided to sit down

The first sentence is rather literary in style: the second is the more widely used. Note that there is not a comma before the and that separates the two participle phrases. It is permissible to insert one if you are in favour of oxford commas. I definitely wouldn't add an oxford comma to your first sentence, because the first participle phrase is so short.

The structure of the second sentence is the same, with two participle phrases preceding the main clause. It's a bit more complicated because each participle phrase contains a lengthy that-clause. The same rules apply, though: a comma is not required, but you can add an oxford comma. Given the length of the two participle phrases, I might be more inclined to add an oxford comma to this sentence.