The Reverend Mark Aitken has been licenced and installed as Master of the Royal Foundation of St Katharine.
The ceremony was led by the Bishop of London, Dr Richard Chartres, and follows Rev Aitken's appointment by the Queen last June.
The foundation is based in Limehouse, in the heart of London's East End, and comprises a retreat and conference centre.
The centre is available primarily to 'not for profit' organisations and provides affordable meeting space.
Rev Aitken joins the foundation from St Lawrence College, Ramsgate, where he was headmaster for eight years.
He has previously served as chaplain at Sherborne School in Dorset and in parish ministry.
He said: "I am delighted to become Master of the Royal Foundation of St Katharine, a venerable institution with roots going back as far as 1147.
"I am particularly looking forward to exploring how the foundation can make a real impact in people's lives, both in the local area and further afield."