Frisian is a group of West Germanic languages spoken in Germany and the Netherlands. There are three main varieties of Frisian: West Frisian which is spoken by about 450,000 people in the Netherlands; North Frisian a collection of nine different dialects spoken in Schleswig-Holstein (Germany) by about 8,000 people, and Sater Frisian with about 2,000 speakers in the German state of Lower Saxony.
Frisian is closely related to English with up to 80% of lexical similarity.
source
wikipedia.org,
omniglot.com,
evertype.com &
ethnologue.com