Complex sentence: On, Baner's camp was attacked by Imperial troops and his army, which was almost surrounded, clearly outnumbered and weakened by casualties, was forced to beat a hasty retreat to Saxony using the shorter route via Bohemian soil, pursued by Imperial cavalry regiments.
Split into simpler sentences: On, Baner's camp was attacked by Imperial troops and his army, which was clearly outnumbered and weakened by casualties, became almost surrounded. Baner was forced to beat a hasty retreat to Saxony using the shorter route via Bohemian soil, pursued by Imperial cavalry regiments.