 Complete the following phrase:  Johnson was born on Salisbury Plantation near current-day Midlothian in Chesterfield County, Virginia, but his family soon moved to Kentucky. He attended the United States Military Academy and graduated after five years of study in 1838. He was commissioned a brevet second lieutet in the 6th U.S. Infantry and was promoted to first lieutet in less than a year. He served in the Seminole Wars in Florida and then in the West. In the MexicanAmerican War, Johnson distinguished himself for action at Veracruz, 