Barbara Mertz (September 29, 1927 – August 8, 2013) http://www.mpmbooks.com/
Barbara Mertz wrote under the pen-name of Elizabeth Peters and Barbara Michaels. I suppose that I will remember her best for her Amelia Peabody series.
The Amelia Peabody stories are set in the late 19th century during the golden age of Egyptology. I highly recommend them.