In 1929, after cataloguing the Shakerley family library, he was asked by a friend in publishing to produce a new biography of Charles II of England. Yale Professor Frank W. Notestein suggested that he begin the work with Charles's escape following the Battle of Worcester, incorporating details of his earlier life into the narrative thereafter. This dramatic opening led the Book Society to choose it as their October 1931 selection, and it became a best-seller. Bryant's success with this volume encouraged him, and he remained in that field. The book has been described as being both readable and informed by solid scholarship. He also regularly continued to produce pageants. These included the Wisbech and Hyde Park pageants, and the Naval Night Pageant in Greenwich, which was attended by the King, Queen, Prince of Wales, British Cabinet, and members of the World Economic Conference. For the quality of his work in this field, he was acclaimed "the English Reinhardt".