More Stately Mansions is set in Massachusetts between 1832 and 1841. The central characters -- Simon Harford, the ambitious son of a wealthy Yankee family; his wife, Sara; and Simon's enigmatic mother, Deborah -- are enmeshed in a triangular struggle for dominance that perfectly embodies the somber central theme of O'Neill's nine-play cycle, A Tale of Possessors, Self-Dispossessed.