Charles II converted on his deathbed, and his brother James II/VII was a Catholic, and tried to repeal the anti-Catholic Test Act (which required government officials to take an oath repudiating various Catholic dogmas). This led to his Protestant daughter's invasion (led by her husband). James fled, and Parliament declared him to have abdicated. After this, the more stringent rules declaring Catholics cannot be King were made, barring Mary's Catholic brother (and his son) from the succession. There were various rebellions in support of this male line, especially when George I, a non-English speaking German distant cousin inherited from the childless Anne, but they always failed. Since then, no British monarch has ever expressed any interest in conversion. Saying this, Charles (the future George VII) has let it be known that he is an atheist. However, he hasn't officially renounced Anglicanism. He's expressed some interest in being "Defender of Faith" rather than "Defender of the Faith", having a multi-denominational crowning ceremony, and so on, but essentially seems happy to accept whatever the government wants. Essentially, now the Anglican church is powerless enough that it doesn't particularly matter.