If you go back to the dawn of time, the Western Maryland was started by a bunch of farmers in Carroll County.
It didn't catch the eye of the Gould Crowd until it reached tidewater at Port Covington in the late 19th century.
They purchased the mortgages held by Baltimore City, a deal engineered by John Mifflin Hood, whose statue stands in St. Paul Place as a result. Hood put together the tapeworm of local rails that ultimately became the east end of the WM.
The West Virginia end was masterminded by Stephen Elkins and Henry Gassaway Davis, in the form of the West Virginia Central and Pittsburgh Ry.
This terminated in Cumberland, the WM terminated in Hagerstown. It took the Gould's money to connect the dots, and then press on toward Pittsburgh with the Connellsville Extension.
It was during the 1920's that the B&O invested in WM stock. They never owned a controlling interest until the B&O merged with the C&O in the early '60's. While the N&W was assembling its Dereco holdings, the WM management was hoping they would be included, but this coincided with the ICC's decision that lifted the voting restrictions from the B&O's WM stock. At that point, the real WM people were replaced by androids from another planet, and the proverbial torocaca hit the fan. When the offices moved from the Commercial Credit building on St. Paul Street, numerous body snatcher pods were discovered in the basement.
Dissenting employees were immediately evaporated by a death ray, with the exception of a few, who were reassigned to clean toilets for Hays Watkins in the Terminal Tower.
Management of the WM then was handed over to the skillful staff of the C&O/B&O.
That's when the heat rays were unleashed, destroying hundreds of miles of tracks, and reducing the Western Maryland to pile of rubble.
It was the only way to make the B&O look halfway decent. By this point, the WM had become a part of the Chessie System, famous for it's cute little kitty mascot...
Anyway, that's the best that my research could come up with. Others may be able to help more.
Lee