Cohen had built his first toy train at age seven, attaching a small steam engine to a wooden locomotive he had carved.

The same year, he was awarded a defense contract from the United States Navy to produce mine fuses, earning $12,000.

[2] Cohen and his associate Harry Grant founded Lionel Corporation in New York City in 1900.

[2] After expanding the production of toy trains and building his business, in 1910 Cohen legally changed his surname to "Cowen", for reasons unknown.

[1] There had been waves of Jewish immigrants from Germany and eastern Europe to the United States, and many others also adopted anglicized names.