Three former Church of England bishops who are opposed to the consecration of women bishops were ordained as Roman Catholic priests in London on Saturday.
The three, John Broadhurst, Andrew Burnham and Keith Newton, are the first traditionalist Anglicans to take up an offer by Pope Benedict.
They were ordained at Westminster Cathedral during a ceremony carried out by the head of the Catholic Church in England and Wales, the Archbishop of Westminster Vincent Nichols.
The bishops became the founding members of the world's first ordinariate, a Church subdivision proposed by the pope in 2009 to let traditionalists convert while keeping some Anglican traditions.
Defections by traditionalists were triggered by the Church of England's decision last year to consecrate women bishops.
The three bishops had to be ordained as Catholic priests because the Vatican does not recognise Anglican ordinations. Married Anglican priests will be accepted but married bishops cannot retain their higher status.
More Anglicans to follow
About 50 priests and 30 groups of parishioners from the Church of England are expected to follow in the first wave and enter full communion with Rome.
Other groups of Anglicans in Australia and North America have expressed interest in the pope's offer, and other ordinariates are expected to be established in other parts of the world.
The pope's offer caused tension between Rome and the Church of England, where many felt the announcement was handled badly and sidelined their spiritual head, the Archbishop of Canterbury Rowan Williams.
Differences appeared to be smoothed over however during the first state papal visit to England and Wales last September when he was received warmly by Williams.
The Catholic Church has set up a fund of £250,000 pounds to help support the new ordinariate, which will be called the Personal Ordinariate of our Lady of Walsingham.
Their patron will be the 19th century English convert John Henry Newman, whose beatification was proclaimed by the pope during his trip.