Complex sentence: Kuhn was president and treasurer of the firm of Kuhn, Cooper, & Geary, once the largest retail shoe store in the South, which earned a reputation as the premiere footwear store in downtown Nashville.
Split into simpler sentences: Kuhn was president and treasurer of the shoe store of Kuhn, Cooper, & Geary. It was once the largest retail shoe store in the South, which earned a reputation as the premiere footwear store in downtown Nashville.