Answer:

Although he was admired by his contemporaries primarily as an outstanding harpsichordist, organist, and expert on organ building, Bach is now generally regarded as one of the greatest composers of all time and is celebrated as the creator of the Brandenburg Concertos, The Well-Tempered Clavier, the Mass in B Minor, and numerous other masterpieces of church and instrumental music. Appearing at a propitious moment in the history of music, Bach was able to survey and bring together the principal styles, forms, and national traditions that had developed during preceding generations and, by virtue of his synthesis, enrich them all.