Is there any difference in meaning?
Are Possessive ’s and of interchangeable?
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Sign up to join this communityThis follows the usual pattern with titles like "Lord", "Duke" or "King". We tend to say:
Duke of York
King of England
and metaphorically
Queen of Hearts
Prince of Thieves
So as a title, the usual structure uses "of", and the possessive "'s" is not equivalent.
It is possible to say "England's king", but as a description and not a title.
Frodo is not the rings' lord or master and never will be. The Lord of the Rings is Sauron.
For inanimates (e.g. the Rings), the form "of the" is preferred to "'s".
Stylistically, the fact that this form emphasizes the Lord rather than the Rings can also explain this choice.