Born in New York City, Beach was graduated from the Yale Law School in 1856. He was admitted to the bar the same year and commenced practice in New York. Took up residence in Orange County, New York, in 1861. He served as member and treasurer of the Democratic State central committee 1877-1879.Beach was elected as a Democrat to the Forty-seventh, Forty-eighth, and Forty-ninth Congresses and served from March 4, 1881, until his death at his home, "Knoll View," Cornwall, Orange County, New York, August 10, 1886. He served as chairman of the Committee on Expenditures on Public Buildings (Forty-ninth Congress). He was interred in Greenwood Cemetery, Brooklyn, New York.
Beach, Lewis was born on March 30, 1835 in New York City.