whom did he marry?
Julia.
Ulysses S. Grant
In Missouri, Grant visited Dent's family and became engaged to his sister, Julia, in 1844. 
who's the 18th president of the united states Ulysses S. Grant. how is he associated with the mexican–american war? He took part in it as a soldier of the American army. which educational institute did he attend? Maysville Seminary , and John Rankin's academy.
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Ulysses S. Grant [SEP] Marriage and family
In Missouri, Grant visited Dent's family and became engaged to his sister, Julia, in 1844. Four years later on August 22, 1848, they were married at Julia's home in St. Louis. Grant's abolitionist father disapproved of the Dents owning slaves, and neither of Grant's parents attended the wedding. Grant was flanked by three fellow West Point graduates, all dressed in their blue uniforms, including Longstreet, Julia's cousin. At the end of the month, Julia was warmly received by Grant's family in Bethel, Ohio. They had four children: Frederick, Ulysses Jr. ("Buck"), Ellen ("Nellie"), and Jesse. After the wedding, Grant obtained a two-month extension to his leave and returned to St.