Elisabeth Christine of BrunswickWolfenbttelBevern was Queen of Prussia from 1740 to 1786 as the spouse of Frederick the Great. By birth, she was a Duchess of BrunswickWolfenbttel. She was also the longest serving queen of Prussia.
Elisabeth Christine was born the daughter of Duke Ferdinand Albert II and Duchess Antoinette of BrunswickWolfenbttel.
Source: Wikipedia