Bach was born into a musical family in Eisenach, the capital of the duchy of Saxe-Eisenach, in present-day Germany. His father, Johann Ambrosius Bach, was the director of the town musicians.

After being orphaned at age 10, he lived for five years with his eldest brother Johann Christoph Bach, the organist at St. Michael's Church in Ohrdruf, Saxe-Gotha-Altenburg. There, he received valuable training from his brother, who instructed him on the clavichord.

In 1700, he was granted a scholarship at St. Michael's for his fine voice. In addition to singing in the choir, he played the school's three-manual organ and harpsichords.

He composed music for the principal Lutheran churches of Leipzig, composing hundreds of four-part harmonizations of Lutheran chorales, as well as several masses, including Mass in B minor, which is among his most popular vocal works.

Baroque music forms a major portion of the "classical music" canon (not to be confused with the Classical period) and is now widely studied and performed. The term "baroque" comes from the Portuguese word barroco, meaning "misshapen pearl."

In 1705, Bach walked 560 miles (from Arnstadt to Lübeck and back again) to hear the famous organist and composer. He was only granted four weeks leave from his position as organist in Arnstadt but angered his employer by taking off four months without permission.

Maria Barbara Bach (1684-1720) was the the composer's first wife. She was also his cousin. Her death in 1720 was a shock to Bach, who was away at Carlsbad with his employer, Prince Leopold. When he left, Maria Barbara was in perfect health, but when he returned two months later, she had already been buried. The cause of her death is undocumented.

It wasn't until the 20th century that Bach's Toccata and Fugue in D minor eclipsed all of his other organ compositions in popularity, thanks in large part to Hollywood producers who began using its thundering organ sounds as a ghoulish shorthand for cinematic terror.

When he heard Bach play in Cassel in 1714, Frederick was so astonished at his virtuosity that he took a diamond ring from his finger and gave it to the composer.

In 1717, Bach tried to quit his job as a chamber musician in the court of the Duke of Saxe-Weimar. The Duke took offense, and Bach was jailed for almost a month for "too stubbornly forcing the issue of his dismissal."