The term 'Diary Keeper' can be summarized by two crossword solutions: PEPYS (5 letters) and SamuelPepys (11 letters). PEPYS is the surname of Samuel PEPYS, an English naval administrator and Member of Parliament who is most famous for his diary. His diary, which he kept from 1660 to 1669, is one of the most important primary sources for the English Restoration period and provides a detailed account of life in London during that time.