The Lake Shore and Michigan Southern Railway Company was formed in 1869, under the laws of the States of New York, Pennsylvania, Ohio, Indiana, Michigan and Illinois, by the consolidation of The Michigan Southern and Northern Indiana Railroad Company with a line from Chicago to Toledo, The Lake Shore Railway Company with a line from Toledo to Erie, and The Buffalo and Erie Railroad Company with a line from Erie to Buffalo. The two first named companies were consolidated on April 6, 1869, under the name of The Lake Shore and Michigan Southern Railway Company, and this company was, on June 22, 1869, consolidated with The Buffalo and Erie Railroad Company, retaining the former name. 1871-2 the following branch mileage was constructed: Sandusky to Oak Harbor, 34.70 miles; Ashtabula to Jamestown, 36.09 miles; and from Sandusky Junction to Old Pier Depot, 3.74 miles.

In 1903, a low grade line was constructed between Plymouth (now Carson), Ohio, and Brookfield, Ohio, 42.59 miles, of which 18.10 miles were built by The Lake Shore and Michigan Southern Railway Company and 24.49 miles by The Mahoning Coal Railroad Company.

The American Locomotive Company delivered 70 “Mikados” to the NYC during 1912 and 1913. Thirty-five of them went to the Lake Shore & Michigan Southern and Thirty-five went to the Michigan Central. Ten of the LS&MS locomotives were delivered in 1912 and were designated as Class H-7a and assigned road numbers 4000-4009. The other 25 were delivered during 1912-1913, were designated as Class H-7b and assigned road numbers 4010-4034. All 70 of these locomotives had 63” drivers, 27” x 30” cylinders, a 190 psi boiler pressure and they exerted 56,100 pounds of tractive effort. By 1917, the 25 designated as Class H-7b were transferred to the Michigan Central and later renumbered NYC road numbers 2035-2059.

There are no surviving Lake Shore & Michigan Southern 2-8-2 “Mikado” type locomotives.