Complex sentence: Bret Harte, chronicler of the California Gold Rush, had founded a monthly literary magazine named the "Overland Monthly" in 1868 while previously various stagecoach companies had incorporated "Overland" into their names.
Split into simpler sentences: Bret Harte, chronicler of the California Gold Rush, had founded a monthly literary magazine named the "Overland Monthly" in 1868. Previously various stagecoach companies had incorporated "Overland" into their names.