John C. Cantwell | |
|---|---|
 | |
| Born | 9 January 1859 Raleigh, North Carolina |
| Died | 8 October 1940 (aged 81) Sausalito, California |
| Allegiance | United States of America |
| Service/ | U.S. Revenue Cutter Service United States Coast Guard |
| Years of service | 1879–1920 |
| Rank | Captain (USRCS) Commander (USCG) |
| Commands |
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| Battles/wars | World War I |
John Cassin Cantwell (9 January 1859 – 8 October 1940) was a United States Coast Guard officer and early United States explorer of Alaska.