Complex sentence: He promptly rejoined Ney, took part in the battle of Lützen and, as chief of the staff of Ney's group of corps, rendered distinguished services before and at the battle of Bautzen, and was recommended for the rank of general of division.
Split into simpler sentences: He promptly rejoined Ney, took part in the battle of Lützen. As chief of the staff of Ney's group of corps, he rendered distinguished services before and at the battle of Bautzen, and was recommended for the rank of general of division.