... once helped the most beautiful woman in the world return home.

Go to Priam's Palace (post-war section)

• Ask Priam Paris >> He'll talk, then tell you to go speak with Menelaus.
• Move S, W, S, S, S to Menelaus
• Ask Menelaus Paris (or just skip straight to Ask Menelaus Helen) >> He'll have some idea for you to help, blah blah.
• Ask Menelaus Yes

Journal Entry "Return Helen to Menelaus of Sparta" is triggered at this point.

• Kill Paris (he's a bit of a headbutt happy jerk at times)
• Aphrodite appears when Prince Paris is almost dead, stopping the fight and stealing Paris away.
• After a couple of echoes of quest flavor, Helen of Troy approaches and asks you to take her to Menelaus.
• Ask Helen I will take you to Menelaus
• Wait for a couple more emotes/equipment giving from her and she'll then follow you.
• Move South

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Alternative Route

• Go to Past Troy, find Paris, and just kinda go that way. Basically same result, but takes longer.