Doug Ewell doug at
Mon Sep 26 19:47:39 CEST 2016

The name "Czech Republic" has been officially changed to "Czechia" in
both the UN M.49 standard and ISO 3166-1, which is formally dependent on

The ISO change is noted in the Online Browsing Platform (OBP); visit and enter "cze" in the search box.
The M.49 change is announced in a note dated today (September 26) on the
UNSD page ( "As of
17 May 2016, the country name 'Czechia' replaces this Member State's
former short name of Czech Republic (code 203)."

See also

The meaning of the ISO 3166-1 code element [CZ] remains the same; only
the name has changed.

RFC 5646, Section 3.1.5 says:

"For subtags taken from a source standard (such as ISO 639 or ISO
15924), the 'Description' fields in the record are also initially taken
from that source standard."


"For fields of type 'language', the first 'Description' field appearing
in the registry corresponds whenever possible to the Reference Name
assigned by ISO 639-3.  This helps facilitate cross-referencing between
ISO 639 and the registry."

Despite the word "initially" in the first passage and the restriction to
language subtags and ISO 639 in the second, it seems reasonable and
consistent to adopt the new official name "Czechia" as the primary
Description field for region subtag 'CZ'. However, given the great
frequency of continued use of the name "Czech Republic" in
English-language contexts, it also seems reasonable to retain the
existing Description field in a secondary position. We previously did
this in 2014 when the official name for region 'CV' was changed from
"Cape Verde" to "Cabo Verde".

Below are a proposed record and registration form to implement this


File-Date: 2016-xx-xx
Type: region
Subtag: CZ
Description: Czechia
Description: Czech Republic
Added: 2005-10-16



1. Name of requester: Doug Ewell
2. E-mail address of requester: doug at

3. Record Requested:

Type: region
Subtag: CZ
Description: Czechia
Description: Czech Republic

4. Intended meaning of the subtag:

5. Reference to published description of the language (book or article):

6. Any other relevant information:

This registration tracks a change made to ISO 3166-1 effective
2016-05-17, changing the English short name for 'CZ' from "the Czech
Republic" to "Czechia". The Description field "Czech Republic" is
retained in the Registry as a secondary description.

Doug Ewell | Thornton, CO, US |

More information about the Ietf-languages mailing list