A statement Thursday announced that Baker will succeed Francis Campbell, who has been transferred to another diplomatic appointment.
Baker noted a developing “strong and fruitful global partnership between the United Kingdom and the Holy See.”
“The historic visit of Pope Benedict XVI in September 2010 reinforced that relationship and opened new avenues for bilateral and multilateral collaboration,” he said.
Baker has been in diplomatic service since 1989, most recently serving in Bolivia.
The Holy See and the United Kingdom just marked the anniversary of restored relations. April 1, 1982, was the day of restoration of full diplomatic relations between the United Kingdom and the Holy See, after a break of some 423 years.