Complex sentence: Meanwhile, Russian and Swedish invasions from the east and north divided Prussia's forces, and in the autumn of 1757 Austrian and French forces attempted to retake Saxony, only to experience a decisive defeat in the Battle of Rossbach on 5 November.
Split into simpler sentences: Meanwhile, Russian and Swedish invasions from the east and north divided Prussia's forces. However, in the autumn of 1757 Austrian and French forces attempted to retake Saxony, only to experience a decisive defeat in the Battle of Rossbach on 5 November.