prepositions - "Nobody but he/him was present"?

1. Nobody but him was present.


2. Nobody but he was present.

Which usage is correct?

I'm having tough time finding out which case of noun/pronoun should I use in a sentence. I know that I/He/She are nominative case while Me/Him/Her are in the objective case.

My thought process goes like this. In the above example:

1. I see the verb "present".


2. I search for the doer of the action. Here it is he/him.



3. I declare he/him should come in nominative case as it is the subject. Therefore, it should come in nominative case (he).

But the correct answer is "him" in a book without giving explanation. Kindly help me solve this nominative/objective case.

Answer

What role does the pronoun play in the sentence?  If it's a subject, it should be in the subjective case.  If it's an object, it should be in the objective case.

As I parse this sentence, "him" is the object of the preposition "but".  The prepositional phrase "but him" modifies the pronoun "nobody".  The nominative phrase "nobody but him" is the subject of the clause.  "Was" is the verb.  "Present" is a predicate adjective.

However, there is an alternate view.  The word "but" can also be a conjunction.  As a conjunction, it would join the subject "nobody" with the subject "he".  As a subject, "he" takes the subjective case.

Since both options are grammatically possible, which should we prefer?

I could say that, in my dialect, the first sounds more natural.  That may be true, but it isn't very helpful.

There is a version of this sentence such that "but" must be a preposition: "Nobody was present but him."  To my ear, this version means the same thing as the original.  For that reason, I recommend treating this instance of "but" as a preposition, and treating "him" as the object of a preposition.