German language skills are not required for the issuance of an EU Blue Card. Exceptions to this are persons who wish to exercise a regulated profession, such as doctors and pharmacists, who must in principle prove German language skills in order to obtain a license to practice their profession.
The settlement permit can be issued after 33 months in the case of basic German language skills (language level A1); this period is reduced to 21 months in the case of proof of sufficient German language skills (language level B1).
As a holder of an EU Blue Card, you are entitled to a permanent residence permit after five years. Not only the periods in Germany are taken into account, but also periods during which you lived in another EU member state.
All stays with the EU Blue Card that were 18 months or longer are taken into account. In addition, you must have resided with an EU Blue Card for two years in the member state in which you are applying for a permanent residence permit.
Spouses of an EU Blue Card holder are entitled to a residence permit without the immigrating spouse having to prove knowledge of German if both spouses are at least 18 years old.