LeGrand Lockwood was born in Norwalk, Conn. in 1820, the fifth son of Benjamin and Elizabeth (Kellogg) Lockwood. By the early nineteenth century, numerous Lockwood descendants owned many residences and businesses in Norwalk, and the Kelloggs and the Lockwoods had adjacent farms on Main Street, north of Union Avenue. This is the area in which Benjamin Lockwood lived with his family until his son, LeGrand, was eleven years old. At the age of 55, LeGrand's father decided to seek his fortune in the garment industry and moved to New York City. He died in Brooklyn in 1852.
Not much is known about LeGrand Lockwood until he started his first job as a clerk at Corning and Co., Brokers, at the age of 18. He must have served a very successful apprenticeship, for he became a partner of Genin and Lockwood, Brokers, when he was only 23. By 1857, Lockwood had formed his own brokerage firm. His successful handling of railroad stock transactions gave him such prominence on Wall Street that in 1863 he was elected Treasurer of the New York Stock Exchange.
His business deals reached far and wide. Between 1862 and 1863, Lockwood made a trip to Europe to sell government bonds, as the Civil War was costing President Lincoln $2,000,000 per day. He started a horse-drawn railcar line in Connecticut, first chartered in 1862, and was director and eventually, controlling stock holder of the Danbury and Norwalk Railroad. This was just the beginning of Lockwood's railroad ventures that had started in the New York-Connecticut area, and later expanded to the Western regions of the country. The successful promotion of the sale of U.S. war bonds abroad, and his involvement in the railroad and steamship businesses made him one of the country's first millionaires.
On June 9, 1842, LeGrand Lockwood married Ann Louisa, daughter of Seth Williston Benedict of New York City. Ann Louisa's father, like Benjamin Lockwood, had left Norwalk in 1832, where he had published the Gazette, to start a new business in New York City. He was publisher of the New York Evangelist by the time his nineteen-year-old daughter married LeGrand Lockwood. The young couple had probably known each other in Norwalk, although the Lockwoods lived on Main Street in the northern part of town, and the Benedicts lived on West Avenue, just south of the Congregational Church in Old Well, or South Norwalk. Two years after they were married, the first of their seven children, LeGrand, Jr. was born, followed by Williston, in 1846. The following year Roswell was born but died as a baby, then Henry, in 1852, Arthur in 1856, Anna Louise in 1858 (she did not survive), Florence in 1859 and Edwin in 1863.