Lemberg was built at Doncaster Works in July 1924 as an LNER A1. He wore the number 2544. Lemberg was one of the first A1s to be rebuilt to an A3, in December 1927. Under Edward Thompsons re-numbering scheme of 1946, he was renumbered 45. During British Railways service, he was numbered 60045. In 1958/9 he was fitted with a Kylchap blast pipe and smoke deflectors. He was finally withdrawn in November 1964 and was scrapped soon after.
The Elderly Brake Van once mentioned Lemberg, along with his sister Pretty Polly, saying they were named after racehorses who won the Derby. He referred to their names as silly for engines.
Lemberg was originally painted in the LNER "Apple Green" livery with black and white lining. He was repainted in the LNER "Wartime Black" livery in 1942. After the war was over, he returned to his original "Apple Green" livery. Upon nationalisation in 1948, he was painted in the experimental BR "Express Passenger Blue" livery with black and white lining until he was finally repainted in BR "Brunswick Green" livery with black and orange lining in 1952.