US Transatlantic Seapost 1921 - 1924

The USA's own "Transatlantic Sea Post Service" after WW I was resumed in 1921. It started as part of the Railway Mail Service section until July 1, 1923, when it came back under the direct control of the "Sea Post Service".
The ships were mostly German ships confiscated after the war and owned by the United States Shipping Board. They were operated here for the "Shipping Board" by the "United States Line".

The ships with the corresponding "Sea Post" number were as follows:
  • Nr. 1 - AMERICA
  • Nr. 2 - GEORGE WASHINGTON
  • Nr. 3 - PENINSULA STATE (renamed in PRESIDENT PIERCE in May 1922 and
    renamed again in PRESIDENT ROOSEVELT in August 1922)
  • Nr. 4 - LONE STAR STATE (renamed in PRES. TAFT in May 1922 and
    renamed again in PRES. HARDING in August 1922)
  • Nr. 5 - RESOLUTE
  • Nr. 6 - RELIANCE
  • Nr. 7 - MANCHURIA
  • Nr. 8 - MONGOLIA (Ex DEUTSCHLAND)
  • Nr. 9 - MINNEKAHDA
  • Nr. 10 - LEVIATHAN (Ex VATERLAND)
  • Nr. 15 - REPUBLIC
There were four different types of postmarks used in this period.

Source references:

Cockrill, Booklett No 54
Hosking, Seaposts of the USA


Foreign postcard franked as required with postmark type A8 to Cockrill with the number 1 in the killer. Postmarked on August 11, 1922 aboard the steamer "AMERICA". Addressed to Gablonz, Czechoslovakia.
As required franked domestic postcard with postmark type A8 to Cockrill with the number 2 in the killer. Postmarked July 01, 1923 aboard the steamer "GEORGE WASHINGTON". Addressed to Providence, R.I.
Foreign postcard franked as required with postmark type A9 to Cockrill with the number 5 in the killer. Postmarked on 12 July 1922 on board the steamer "RESOLUTE". Address too faint - only "Germany" legible.
Foreign postcard franked as required with postmark type A10 to Cockrill with the number 10 in the killer. Postmarked on 09 May 1924 aboard the steamer "LEVIATHAN". Addressed to Long Island City.
Foreign postcard franked as required with postmark type A10 to Cockrill with the number 15 in the killer. Postmarked on 09 December 1924 aboard the steamer "REPUBLIC". Addressed to Long Island City.
Registered mail posted at the board post office of the steamer "LEVIATHAN". Postmark type A10. The number is not recognizable, but must be a 10. Postmarked 20 October 1923. Addressed to Karlsruhe, Germany.
Reverse: Registered postmark of the "US Sea Post" and arrival postmark of Karlsruhe dated November 2, 1923.


Copyright J├╝rgen Kuseler 2021