fifth-century B.C. Athenian democracy, or fifth century B.C. Athenian democracy?

[Wherefore]

Hi, this is the first time that I post here. I have two related questions.

First, I have been uncertain which of the following is right, even though I have seen all of them except for (6):

(1) fifth-century B.C. Athenian democracy

(2) fifth century B.C. Athenian democracy

(3) fifth-century-B.C. Athenian democracy

(4) the fifth-century B.C. Athenian democracy

(5) the fifth century B.C. Athenian democracy

(6) the fifth-century-B.C. Athenian democracy

Secondly, I am unsure whether "the Athenian democracy" or just "Athenian democracy" is the right expression. Again, I have seen both of them.

Thank you very much in advance for your help.

[Beeesneees]

3 and 6 are incorrect.
The others are acceptable.
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Cheers m' dears!

[Wherefore]

Thank you, Beeesneees.

But I still don't understand why "fifth-century B.C. Athenian democracy" or "Athenian democracy" is both correct with or without the article "the"....

[Beeesneees]

It's context dependent.
Are you aw3are that sometimes the earth/the sun/the moon/the spring, etc. is used whereas other times the nouns do not take the article?
It's basically the same principle here.
_________________
Cheers m' dears!

[Wherefore]

Thank you.

Oh no! Actually I am not aware of any principles of omitting "the" before sun/moon/etc!

I have seen only the usage of the sun/the moon, but not sun/moon. I assume the former is the normal usage?

And if so, does this mean that "the Athenian democracy" is more likely to be the normal usage than "Athenian democracy"?

[Beeesneees]

It really depends on the context.

This explains in more detail:
http://learnenglish.britishcouncil.org/en/english-grammar/determiners-and-quantifiers/definite-article
_________________
Cheers m' dears!