Daughter of Karl I of Brunswick and Phillipine Charlotte of Prussia. On July 14, 1765, she married Frederick William, who later became the King of Prussia. They had one daughter, Frederica Charlotte (1767-1820), who later became Duchess of York, but their marriage was dissolved in 1769 due to adultery on both sides.
Following the divorce, Elisabeth Christine was initially exiled to Küstrin Fortress and then placed under house arrest in the Ducal Castle of Stettin, under care of her cousin, Duke Augustus William of Brunswick-Bevern. She was also demoted from Royal Highness to Serene Highness.
During her early years of confinement, she struggled with the isolation due to her extroverted personality. To alleviate her loneliness, she reportedly arranged chairs in a row to dance between them. She once planned an escape to Venice with the help of an officer, but the plan fell through when the officer disappeared. Her living conditions were later improved by King Frederick, and in 1774, she received a summer residence in Jasenitz.
Following the death of Frederick the Great in 1786, her situation further improved; she was allowed visitors, and outdoor activities. Mirabeau noted that she declined an offer for release, having adapted to her life in confinement. In one instance, she slapped an officer for trying to open a personal gift, leading to a dismissive response from the king when the officer complained.
Throughout her later years, she was visited only by King Frederick William IV. When the French army occupied Stettin in 1806, she relocated to a small estate outside the city, naming it Landhaus Friedrichsgnade.
Elisabeth Christine died at 93, outliving her immediate family and her former husband. At her death, the city's bells tolled in her honor. She had arranged for a private mausoleum in her park, preferring not to be buried with her relatives in the Ducal Brunswick Crypt. Following a change in the park's ownership, her remains were moved to the Chapel of the Ducal Castle of Stettin on July 19, 1849, although some sources claim she was later reinterred in the cathedral of Krakow.
Boswell danced with Princess Elisabeth at the court of Brunswick on August 13, 1764. Following his last night in Brunswick, August 21, he wrote that "I must not forget to mark that I fell in love with the beauteous Princess Elizabeth. I talked of carrying her off from the Prince of Prussia, and so occasioning a second Trojan War."