Cromwell guitars and mandolins were made by Gibson in the mid to late 1930s and distributed by mail order catalog companies like Grossman Music Inc. (Cleveland), Richter and Phillips and Continental Music (Chicago). Gibson introduced these cheaper brands (like Bellson, B&S Barrington, Oriole, Cromwell, Kalamazoo, Ambassador, Capital, Carson Robison, Ray Whitley, Andy Sannella, Fascinator, Francis Day & Hunter, Grinnell, Hayden, Kel Kroydon, Martelle, Marshall Special, Henry L. Mason, Mastertone Special, Mitchell Brothers, Old Kraftsman (Spiegel), Montgomery Wards/Recording King, Reznick Radio Special, S.S. Stewart, Trujo & Truett, Washburn, and Werlein Leader) due to the depression which hurt sales of the high end Gibson own-branded instruments.

Source: Gruhn's Guide to Vintage Guitars. George Gruhn. 1999

Source: Fox guitars - the other brands of Gibson (5 February 2017)