A restrictive definition may describe northern Europe as being roughly north of the southern coast of the Baltic Sea, which is about 54°N, or may be based on other geographical factors such as climate and ecology.
[1] In the UN geoscheme, the following countries are classified as being in northern Europe:[1] as well as the dependent areas: EuroVoc is a multilingual thesaurus maintained by the Publications Office of the European Union, giving definitions of terms for official use.
The system provides clear definitions and codes for recording plant distributions at four scales or levels, from "botanical continents" down to parts of large countries.
A number of Celtic languages are spoken in the British Isles including the Brythonic Welsh and the Goidelic Scots Gaelic and Irish.
[13] The Norman languages of Jèrriais and Guernésiais are spoken in Jersey and Guernsey, though are listed as endangered due to the increasing prominence of English in the islands.
[13] During the Early Middle Ages, the Roman Catholic Church expanded into northern Europe and spread Christianity among the Germanic peoples.
The Latin alphabet along with the influence of Western Christianity spread northward from Rome, leading to written English, German, Dutch, Danish, Norwegian, Swedish, Icelandic, Latvian, Lithuanian, Estonian, Finnish and Sámi languages.