Many of these cantatas were written for inclusion in the weekly worship services. In Bach's day, a typical church service could last for 3 or 4 hours. The cantatas were presented usually after the...
195
Between 1704 to 1740 Bach composed cantatas for the churches that he served. He is believed to have written over 300, although only 195 have been preserved.
Yes he did, but they are usually referred to as "Sinfonia" in Bach's time and were not on such as a grand scale as later works.
During the Baroque Era, the "Symphony" was in its developmental stages...