Louis McLane, the son of Louis McLane and Catherine Mary Milligan, was born in Wilmington, Delaware, on January 20, 1819. After attending St. Mary's College and Newark College, he served as an officer in the United States Navy between 1835 and 1850. He then lived in California, where he entered the steamship business, and later served as a manager for Wells, Fargo & Company in San Francisco. Around 1866, he moved to New York City, and, in 1868, he moved to Baltimore, Maryland. McLane married Sophie Latimer Hoffman (b. 1827), the daughter of Baltimore resident Samuel Hoffman, in 1849. They had 8 children: Catherine, Sophie, Elizabeth, Louis, Hoffman, Emily (or Emma), Sarah (or Sally), and Charles.