"(Qtd. Man 132) He was placed transferred into active service in 1833 and promoted to first- lieutenant in his new regiment the First Dragoons. However, his family saw that he was destined for something greater than a purely militaristic career. After the coaxing of his family for sometime and partially due to his reoccurring illnesses, he gave in to his family's wishes. He resigned from the military on June 30, 1835.(Chadwick 189).
Soon after his resignation he began a relationship with a Miss Sallie Knox Taylor, the daughter of the future president Zachary Taylor. They were married at the home of Taylor's aunt; however, less than a year after their marriage, his new bride was stricken with malaria and died shortly thereafter.(Man 245) This devastated Davis, but he continued his new life as a cotton planter in Mississippi and studied politics in order to prepare himself for his future career. His brother Joseph presented Jefferson with a plantation adjoining to his own home on the Mississippi River. The plantation would come to be known as Brierfield Plantation. Davis came to be the owner of one-hundred and seven slaves. One of his closest friends was also one of his slaves, a man by the name of James Pemberton.(Chadwick 179) Davis was remarried in 1845 to the daughter of a wealthy plantation owner. Her name was Varina Howell. With his new wife he had five children, three sons and two daughters. All three of his children died before the age of twenty-two.(Man 134) .
The same year that he was married he was also elected as a democrat to Congress. He cut his term in office short in order to lead a Mississippi regiment in the Mexican War. He fought in such battles as Monterrey and Buena Vista and found himself a decorated war veteran when it was all over. The gallantry exhibited in his leadership also won him the respect of the entire army. At Buena Vista, however, he was wounded but refused to leave the battlefield until the front had been won.