Complex sentence: It took place in the valley of the Côa River and it was the first significant battle for the new army of 65,000 men controlled by Marshal André Masséna, as the French prepared for their third invasion of Portugal.
Split into simpler sentences: It took place in the valley of the Côa River. It was the first significant battle for the new army of 65,000 men controlled by Marshal André Masséna, as the French prepared for their third invasion of Portugal.