Complex sentence: Kenneth was killed in France and in 1927 Alan was brought into the company as an equal partner with his father, and in 1938 inherited the business, bringing his son Peter in as a partner in 1946.
Split into simpler sentences: Kenneth was killed in France and in 1927 A. was brought into the company as an equal partner with his father. With the death of Hermann Koeppen-Wendt in 1938, his son A. inherited the business then brought his son Peter in as a partner in 1946.