Helvetia is the Latin name for Switzerland. They speak German, French and Italian, so it is rather confusing! Rather than try to use the three official languages of Switzerland they use the Latin.
Switzerland
Switzerland - official name: CH, confoederatio helvetica
Helvetia is the name of Switzerland in Latin. It is a compromise on marking stamps for a country with so many languages. It avoids multiple names in different languages.
Gutter
Philatelists collect stamps and postal history.
Helvetia
Helvetia
Switzerland has four languages, but to avoid favouring any group, the name of the country on currency and stamps is given in Latin - Helvetia. On a Swiss car the national identifier is CH for Cantones Helvetiae.
Italy
Vet Boswell's birth name is Boswell, Helvetia.
The Republic of Sudan.
Great Britain does not print their name on their postage stamps. The name of the country is not mentioned because United Kingdom was the first country in the world to start postage stamps. However, all of the postage stamps have at minimum a silhouette of the current Queen (or King).
The official name of Switzerland is Latin, so as not to offend speakers of the four different languages in the country. Helvetia was the Latin name for the area, but now it is a federation of Cantons, so the official name is Cantones Helvetiae, Cantons of Helvetia.