[1] It was built under the direction of the road's master mechanic George Emerson, and said to have been inspired by the Great Western Railway locomotive 6000 King George V which had appeared at B&O's 1927 Fair of the Iron Horse.

It was constructed to haul a new lightweight train, the Royal Blue, between New York City and Washington, D.C. Later that year it was sent to the B&O-owned Chicago and Alton Railroad.

It returned to the B&O in 1942 during World War 2 and, after work in the Baltimore and Ohio Railroad's shops, was renumbered to #5340 and assigned to service between Washington, D.C. and Cumberland, Maryland.

Shortly afterward, it was withdrawn from service and stored at the railroad's shops in Baltimore, Maryland, and was scrapped in 1949.

In 1933, Baltimore and Ohio Railroad rebuilt P-1c Pacific #5047 as a Class V1 4-6-4 at its Mount Clare Shops in 1933, keeping the same number #5047.