It's no mystery that she was born in 1890 in Devon, England, wrote 67 novels under this name & 6 as Mary Westmacott
[DOC] [TLE] Agatha Christie is born - Sep 15, 1890 - HISTORY.com [PAR] All told, Christie wrote some 80 novels, 30 short story collections, and 15 plays, 
plus six romances under the pen name Mary Westmacott.