Bach - Brandenburg Concerto No. 1 In F Major, BWV 1046

Musicians in Bach's era were treated much as any other servant by many of the royals that employed them.  So it was inevitable that a musician such as Bach would have his share of difficulties. Sometimes it was not the royals that gave him as much trouble as the city councils in the towns he was employed. Bach could be headstrong, as his focus was on giving the best music performances possible, while many members of the city councils couldn't understand why he couldn't make do with what the previous head musician in their employ did. But Bach proved to be shrewd as well as headstrong in his desire to get and keep the musical reputation he strove for. He prevailed more often as not. 

He had a wide reputation as the most knowledgeable musician concerning the organ. He earned extra money by traveling and assessing organs and what was needed to repair theme, as well as working as a consultant when new organs were being built. In the process, he would demonstrate by playing the organ in question, and as he was known as the best organist in the area, his reputation grew. He made contacts which aided him in his negotiation for future positions.

Bach also knew how to talk the talk of the era to royals. He sent the set of 6 concertos
(in his own handwriting) that are now called The Brandenburg Concertos to Christian Ludwig, Margrave of Brandenburg-Schwedt in 1721, while he was still employed by Leopold, Prince of Anhalt-Köthen. Bach had been hired by the Prince in 1717, and as the Prince was a lover of music, Bach did well there. But when the Prince got married in 1720 to a woman that didn't care for music, the importance of music in the court began to diminish. So Bach went job hunting, and along with the 6 concertos (a quite impressive resume), he sent along a dedication to the Margrave originally in French:

Since I had a few years ago, the good luck of being heard by Your Royal Highness, by virtue of his command, & that I observed then, that He took some pleasure in the small talents that Heaven gave me for Music, & that in taking leave of Your Royal Highness, He wished to make me the honor of ordering to send Him some pieces of my Composition: I therefore according to his very gracious orders, took the liberty of giving my very-humble respects to Your Royal Highness, by the present Concertos, which I have arranged for several Instruments; praying Him very-humbly to not want to judge their imperfection, according to the severity of fine and delicate taste, that everyone knows that He has for musical pieces... 

It took two years from the time the Margrave ordered Bach to send him some compositions until they were sent, and they weren't specially composed for the Margrave. There is musicological evidence that shows the concertos had been written earlier. Whether Bach was honestly considered for the job or not is not known. What is known is that Bach took the job of Cantor in Leipzig in 1723, and stayed there the rest of his life. Whether the Margrave acknowledged the gift or had them performed isn't known. 

There was no standardized orchestra in Bach's time. He would write for the instruments that were available to him. The instrumentation for this concerto is 3 oboes, bassoon, 2 horns (natural horns with no valves), violino piccolo, violin I and II, viola, cello, violone (double bass of the viol family of stringed instruments) and continuo. This is the only concerto of the set that is in 4 movements.

I. Allegro -  This movement, along with the second movement was used in 1713. Bach rewrote the movement to include the violino piccolo. The movement begins with the hunting horns playing traditional hunting calls as the rest of the orchestra plays. Instruments take their turn in presenting themes while the horns punctuate the background with triplets. But the horns are more than an accompaniment; they have their time in the spotlight presenting themes as well, and never fade in the background much. One of the most distinguishing characteristics of this movement is the role the horns play in the ensemble, and even in the disruption of it.

II. Adagio -  A solo oboe begins this movement, followed by the violino piccolo, a small violin that was tuned a minor third above a standard violin. These two instruments play off each other in a duet that is accompanied by the orchestra, minus horns. At the end, the falling notes of the bass alternate with the oboes and strings.

III. Allegro - The violino piccolo has solo material throughout this movement with a wonderful chugging rhythm in the bass. A distinctive touch is when the music comes to a slowdown with two bars of adagio tempo before the music resumes its original speed. Some musicologists believe this music first turned up in a previous cantata. 

IV. Menuet - Trio, Menuet da capo: Polacca, Menuet da capo: Trio II, Menuet da capo - In writing technique, all the movements are in the mood of the concerto grosso, but in form they resemble the multiple orchestral suites of the time. The final movement is a graceful minuet, and after the trio for bassoon and oboes is done, a reprise of the menuet would usually end the movement. But Bach adds two more sections; a Polacca (Italian for Polonaise, a Polish dance) for strings, a reprise of the minuet, and a second trio for horns and oboes. One more reprise of the minuet brings the concerto to an end.