After the coup d'etat of April 29–30, 1918, and the coming to power of Hetman P. Skoropadsky, the People's Republic was abolished, and Ukraine was proclaimed the Ukrainian State. The Ukrainian postal administration had substantial stocks of such stamps. To use them and to prevent identical stamps from other regions from entering circulation—which would have harmed the Ukrainian treasury—on August 20, 1918, the Hetmanate Ministry of Posts decided to overprint all available stocks of Russian stamps with the Ukrainian state emblem, the trident of Saint Volodymyr.
It was impossible to do this centrally under civil-war conditions. Therefore, the overprints were applied by local authorities simultaneously in all postal districts, using whatever technical means were available, often by hand. This resulted in a great variety of overprint types and graphic designs.
Research identified 52 basic trident types, 68 variants, and 13 printing errors—133 major varieties in total. The overprints were made in six postal districts: Kyiv, Poltava, Kharkiv, Katerynoslav, Odesa, and Podillia.
Ukrainian provisional postage stamps began to be forged as early as late 1918 in southern Ukraine, and later counterfeiters were produced by speculators abroad. They forged overprints and postal cancellations and even created non-existent denominations, so-called "fantasy" issues. The Union of Philatelists of Ukraine in Germany successfully identified these forgeries.