Elizabeth Peters was born Barbara Louise Gross on September 29, 1927, in Canton, Illinois, the daughter of Earl Gross and Grace (Tregellas) Gross. She attended the Oriental Institute of the University of Chicago, where she studied Egyptology. Peters received a bachelor of philosophy degree in 1947 and a master of arts degree in 1950, the same year she married Richard R. Mertz. She completed her doctorate in 1952 with a dissertation titled “Certain Titles of the Egyptian Queens and Their Bearing on the Hereditary Right to the Throne.” Following a pattern typical of her generation, Peters worked after marriage as a typist and secretary before having a baby. She followed her husband to various cities in the United States and abroad, cities that she would later use as settings in her fiction both as Elizabeth Peters and as Barbara Michaels.
Under her own name, Peters published two popular books about Egypt, one in 1964 and another in 1966; her first Barbara Michaels book was published in 1966. When her editor suggested that she write more lighthearted books about modern heroines using exotic locales, she borrowed the names of her two children, Elizabeth and Peter, to form her new pseudonym. A true storyteller, she has produced at least a book per year. Peters was divorced in 1969. Her two-hundred-year-old stone house outside Frederick, Maryland, reportedly houses cats, dogs, antiques, and a ghost.
A former president of the American Crime Writers League, Peters has been a member of the editorial board of The Writer, the editorial advisory board of KMT, A Modern Journal of Ancient Egypt, and the board of governors of the American Research Center in Egypt. In 1989, Hood College named her an honorary Doctor of Human Letters. In 1990, she won the Agatha for best novel for Naked Once More (1989), and in 1998 the Mystery Writers of America named her a Grand Master.