The abbey was restored to the Benedictines under the Catholic Mary I of England, but they were again ejected under Elizabeth I in 1559. In 1560, Elizabeth re-established Westminster as a "Royal Peculiar" – a church of the Church of England responsible directly to the Sovereign, rather than to a diocesan bishop – and made it the Collegiate Church of St Peter (that is, a non-cathedral church with an attached chapter of canons, headed by a dean.) The last of Mary's abbots was made the first dean.
The abbey wasn't regiven to the Benedictines under whom?
{'text': 'Mary I of England', 'answer_start': 62}