USRC Ewing, sometimes referred to as USRC Thomas Ewing, was a United States Revenue–Marine cutter with a topsail schooner rig that was constructed in Baltimore, Maryland in 1841.

[1] From the period beginning in December 1845 to April 1846 Ewing sailed over three thousand miles, boarded 62 vessels, and provided relief and supplies to seven.

[4] During the Mexican-American War, on 9 August 1849 Ewing was chosen by Captain John Adams Webster as his flagship in his role as commodore of the Revenue-Marine Atlantic Squadron.

[5][2] The squadron was assigned by the service to assist the Army and Navy by transporting supplies and troops, blockading of Mexican ports, towing, and carrying mail and dispatches.

[5] During the battles of Monterrey and Buena Vista, the cutters Ewing and Legare carried one thousand rifles to General Zachary Taylor at Point Isabel.