He was a son of John I and his wife, Luitgard of Henneberg (1210-1267), a daughter of Count Poppo VII of Henneberg.
He ruled jointly with his brother Henry I.
He may have married a daughter of Nicholas I of Werle, but no record of such a marriage, or any children, has survived.
Albert I died in 1265 and was buried in the Doberan Minster.
This article about a member of the German nobility is a stub.