The house was originally called "Blackacre" and was purchased with a gift from Olave Baden-Powell's father in 1918.

[3] Baden-Powell changed the name of the house to Pax (Latin for Peace) to correspond with the virtues of the Scout Movement.

The west wing was designed by Robert Baden-Powell himself and he also modelled the frieze for the new bathroom, depicting fish in the River Wey.

The following year, due to World War II, Pax Hill was occupied by Canadian military troops and Olave Baden-Powell was required to leave.

[7] After World War II, Olave Baden-Powell gave Pax Hill to the Girl Guides Association (now Girlguiding UK) to be used as a centre for members from the Commonwealth of Nations.