It is headed by the Apostolic Nuncio to Canada, which is both an ecclesiastical and diplomatic office, with the rank of ambassador.

[2] The nunciature was based in a building on Queen Elizabeth Driveway until it purchased Rockcliffe House in 1962.

The first home on the property, built by Duncan Reynier MacNab in 1838–39, was named "Rockcliff House" for its location.

It remained in the Keefer family 1929 when it was purchased by Cairine Wilson, the first Canadian woman to be named to Senator and her husband Norman.

[3] The house was included amongst other architecturally interesting and historically significant buildings in Doors Open Ottawa, held June 2 and 3, 2012.