Original sentence: Dominated largely by Conservative ministers who served under Chamberlain's National Government between 1937 and 1939, the additions of Lord Hankey (Liberal and a former Cabinet Secretary from the First World War) and Winston Churchill (strong anti-appeaser) seemed to give the Cabinet more balance
Edited sentence: Dominated largely by Conservative ministers who served under Chamberlain's National Government between 1937 and 1939, the additions of Lord Hankey (a former Cabinet Secretary from the First World War) and Winston Churchill (strong anti-appeaser) seemed to give the Cabinet more balance