Complex sentence: Cooper was a prominent local business leader, starting in his father's mercantile business, later became the president of the Bank of Oxford, and was instrumental in establishing the Blue Springs Cotton Mill and the Oxford Oil Mill, as well as other business ventures.
Split into simpler sentences: Cooper was a prominent local business leader, starting in his father's mercantile business. He later became the president of the Bank of Oxford, and was instrumental in establishing the Blue Springs Cotton Mill and the Oxford Oil Mill, as well as other business ventures.