Under which monarch did England temporarily return to Catholicism?

Answer 1

Mary I, who reigned from 1553-58, was a staunch Catholic and executed so many Protestants that she was known as Bloody Mary. She renacted the act that allowed heretics (non-Catholics) to be burnt to death tied to a stake.

Answer 2

The Catholic Church was never "restored" in England, the Church of England still owns most of its Churches, and its monasteries and convents were all converted to private homes in the sixteenth century. King George III was the first King, after the protestant revolt, to allow citizens to attend Mass.

from the website History of the Catholic Church in England (16th - 19th Century):

After Catholic worship became legal in 1791, most of the country-house chapels were closed and the missions moved to the nearest towns, following the shifts of population caused by the Industrial Revolution. So Catholic churches are now mostly in cities and towns and date from the last two hundred years. For a survey of them, see A Glimpse of Heaven by Christopher Martin & Alex Ramsey (English Heritage, 2006). At the same time, because of the French Revolution, the English colleges and monasteries on the Continent moved back to England. By the Emancipation Act of 1829 Catholics recovered most of the rights enjoyed by their fellow-citizens. In the 1840s they were much augmented by Irish Immigration after the Famine and by Tractarian converts from the Church of England, who included the future Cardinals Newman and Manning.