Abstract
Religion matters in foreign policy as much as it does in domestic society and, to understand the world in which we live, we have to comprehend religion as a source of influence and motivation in people's lives. That is not always easy for foreign policy specialists and diplomats. Britain's relations with the Holy See go back to 1479 when England sent its first resident ambassador overseas. The Holy See is one of the world's most global bodies—touching directly 17.5% of the world's population through the Catholic Church. It is a unique hybrid of the global and the local, which helps to form global public opinion. Today, the UK's oldest embassy is working on a whole range of issues with the Holy See from tackling climate change, disarmament, international development, interfaith dialogue and preventing and ending conflict.