Select the best word for the blank in the following sentence.
The children learned that the _______ is sometimes considered a turning point of the war.

The Siege of Vicksburg was a battle in the American Civil War and it is considered a proper noun. Proper nouns are people, places, organizations, and sometimes things and they must be capitalized. Prepositions (words like as, at, by, for, in, of, on, per, and to), are not typically capitalized unless they begin a sentence