Czech

Czech Republic (Czechia) Slovakia (This is an official link to the Czechoslovak Summer Time Act of March 8, 1946 that authorizes the Czechoslovak government to set the exact dates of change to summer time and back to Central European Time. The act also implicitly confirms Central European Time as the official time zone of Czechoslovakia and currently remains in force in both the Czech Republic and Slovakia.) (This is a link to the original legislative proposal dating back to February 22, 1946. The accompanying memorandum to the proposal says that an advisory committee on European railroad transportation that met in Brussels in October 1945 decided that the change of time should be carried out in all participating countries in a strictly coordinated manner....) The source for Czech data is: Kdy začíná a končí letní čas. Its main text disagrees with its quoted sources only in 1918, where the main text says spring and autumn transitions occurred at 02:00 and 03:00 respectively (as usual), whereas the 1918 source "Oznámení o zavedení letního času v roce 1918" The tzdata source notes: 00 and 02:00 respectively. As the 1918 source appears to be a humorous piece, and it is unlikely that Prague would have disagreed with its neighbors by an hour, go with the main text for now. We know of no English-language name for historical Czech winter time; abbreviate it as "GMT", as it happened to be GMT.