What pen name did Agatha Christie use for her romance novels?

Agatha Christie used the pen name Mary Westmacott for her romance novels.

Under the Westmacott name, Christie published six mainstream novels that focused more on emotional relationships, family conflict and personal psychology than on crime-solving. The first was Giant’s Bread, published in 1930; the final one was The Burden, published in 1956.

Christie used the pseudonym to separate these intimate, often tragic novels from her detective fiction and to give herself freedom to explore what she called her more private imaginative territory. The books initially attracted attention without immediately revealing that their author was the famous mystery novelist.

Her identity as Westmacott became public in 1949, after a journalist disclosed it. Christie nevertheless continued to publish two more novels under the name. Mary Westmacott is sometimes confused with other Golden Age mystery writers, such as Dorothy Sayers or Ngaio Marsh, but neither was Christie’s romance pseudonym.