Johann Ernst Bach was a cousin far away from the cantor of Leipzig. His back grandfather and the grandfather of Johann Sebastian Bach was brothers.

He was baptized on January 30th, 1722 him also with Eisenach of which he attended the Latin school as from 1732. It is found pupil of his famous cousin in Thomasschule of Leipzig to which it is registered on January 16th, 1737. Inconstant, Johann Ernst leaves St Thomas quickly to follow courses of right to the university but, there still, it gives up and joined Eisenach to replace there his father with the organ of Georgenkirche. Johann Ernst marries Florentina Catharina Malschin there on October 21st, 1750 which will give him 8 children.

It deals also a time with the organ of the court but is destined for Weimar to reorganize the local musical life there. The authorities will devote it at the beginning of February 1756 Kapellmeister but it will be constrained to leave 2 years later, the vault indeed was dissolved.

Johann Ernst finds the organ of Eisenach and finishes its career while inheriting the post of treasurer of benefit of the worship.

It dies out with Eisenach where it is buried on September 3rd, 1777.