SS John Cadwalader was a coastal passenger and cargo steamer launched in March 1926 by Pusey & Jones Corporation, Wilmington, Delaware for the Baltimore-Philadelphia Steamship Company for operation on overnight service between Baltimore and Philadelphia.

The ship was Pusey and Jones Corporation hull number 394, contract 1030,[note 2] with keel laid 11 November 1925 for the Baltimore-Philadelphia Steamship Company as a passenger and cargo vessel intended for operation on overnight, inland passage service between Baltimore and Philadelphia using Chesapeake Bay, the Chesapeake and Delaware Canal and Delaware Bay.

[1][2][3][4][5] John Cadwalader, U.S. Official Number 226007 with home port of Baltimore, had a steel hull, divided by six watertight bulkheads, that extended to the main deck topped by a wooden superstructure.

Evaluations made by government agents on requisition in 1942 noted the vessel was narrow and top heavy making it unsuitable for operation outside sheltered waters.

[4][note 3] John Cadwalader was operated by the Baltimore-Philadelphia Steamship Company in overnight passenger and freight service between Baltimore and Philadelphia from 1926 to 1931.

Ericsson operated the vessel for the company until financial difficulties in 1935 caused a foreclosure on the mortgage of John Cadwalader by the Philadelphia National Bank.

The passenger accommodations elsewhere were unchanged when the ship was laid up in Philadelphia 15 November 1941 due to increased competition from trucking and war time conditions.

[9] John Cadwalader was destined to join other antiquated river and coastal vessels in a convoy designated RB-1[note 4] but burned at the pier in Philadelphia 29 August 1942 while loading.