The reign of James I (1603–1625) was marked by a measure of tolerance, though less so after the discovery of the Gunpowder Plot conspiracy of a small group of Catholic conspirators who aimed to kill both King and Parliament and establish a Catholic monarchy.
A mix of persecution and tolerance followed: Ben Jonson and his wife, for example, in 1606 were summoned before the authorities for failure to take communion in the Church of England, yet the King tolerated some Catholics at court; for example George Calvert, to whom he gave the title Baron Baltimore, and the Duke of Norfolk, head of the Howard family.

The reign of Charles I (1625–49) saw a small revival of Catholicism in England, especially among the upper classes.
As part of the royal marriage settlement Charles's Catholic wife, Henrietta Maria, was permitted her own royal chapel and chaplain.
Henrietta Maria was in fact very strict in her religious observances, and helped create a court with continental influences, where Catholicism was tolerated, even somewhat fashionable.
Some anti-Catholic legislation became effectively a dead letter.
The Counter-Reformation on the continent of Europe had created a more vigorous and magnificent form of Catholicism (i.e., Baroque, notably found in the architecture and music of Austria, Italy and Germany) that attracted some converts, like the poet Richard Crashaw.
Ironically, the explicitly Catholic artistic movement (i.e., Baroque) ended up "providing the blueprint, after the fire of London, for the first new Protestant churches to be built in England".

While Charles remained firmly Protestant, he was personally drawn towards a consciously "High Church" Anglicanism.
This affected his appointments to Anglican bishoprics, in particular the appointment of William Laud as Archbishop of Canterbury.
How many Catholics and Puritans there were is still open to debate.

Religious conflict between Charles and other "High" Anglicans and Calvinists – at this stage mostly still within the Church of England (the Puritans) – formed a strand of the anti-monarchical leanings of the troubled politics of the period.
The religious tensions between a court with "Papist" elements and a Parliament in which the Puritans were strong was one of the major factors behind the English Civil War, in which almost all Catholics supported the King.
The victory of the Parliamentarians meant a strongly Protestant and anti-Catholic (and, incidentally, anti-Anglican) regime under Oliver Cromwell.

The restoration of the monarchy under Charles II (1660–85) also saw the restoration of a Catholic-influenced court like his father's.
However, although Charles himself had Catholic leanings, he was first and foremost a pragmatist and realised the vast majority of public opinion in England was strongly anti-Catholic, so he agreed to laws such as the Test Act requiring any appointee to any public office or member of Parliament to deny Catholic beliefs such as transubstantiation.
As far as possible, however, he maintained tacit tolerance.
Like his father, he married a Catholic, Catherine of Braganza. (
He would become Catholic himself on his deathbed.)

Charles' brother and heir James, Duke of York (later James II), converted to Catholicism in 1668–1669.
When Titus Oates in 1678 alleged a (totally imaginary) "Popish Plot" to assassinate Charles and put James in his place, he unleashed a wave of parliamentary and public hysteria which led to anti-Catholic purges, and another wave of sectarian persecution, which Charles was either unable or unwilling to prevent.
Throughout the early 1680s the Whig element in Parliament attempted to remove James as successor to the throne.
Their failure saw James become, in 1685, Britain's first openly Catholic monarch since Mary I (and last to date).
He promised religious toleration for Catholic and Protestants on an equal footing, but it is in doubt whether he did this to gain support from Dissenters or whether he was truly committed to tolerance (contemporary Catholic regimes in Spain and Italy, for example, were hardly tolerant of Protestantism
The reign of James I (1603–1625) was marked by a measure of tolerance, though less so after the discovery of the Gunpowder Plot conspiracy of a small group of Catholic conspirators who aimed to kill both King and Parliament and establish a Catholic monarchy. A mix of persecution and tolerance followed: Ben Jonson and his wife, for example, in 1606 were summoned before the authorities for failure to take communion in the Church of England, yet the King tolerated some Catholics at court; for example George Calvert, to whom he gave the title Baron Baltimore, and the Duke of Norfolk, head of the Howard family.
The reign of Charles I (1625–49) saw a small revival of Catholicism in England, especially among the upper classes. As part of the royal marriage settlement Charles's Catholic wife, Henrietta Maria, was permitted her own royal chapel and chaplain. Henrietta Maria was in fact very strict in her religious observances, and helped create a court with continental influences, where Catholicism was tolerated, even somewhat fashionable. Some anti-Catholic legislation became effectively a dead letter. The Counter-Reformation on the continent of Europe had created a more vigorous and magnificent form of Catholicism (i.e., Baroque, notably found in the architecture and music of Austria, Italy and Germany) that attracted some converts, like the poet Richard Crashaw. Ironically, the explicitly Catholic artistic movement (i.e., Baroque) ended up "providing the blueprint, after the fire of London, for the first new Protestant churches to be built in England".
While Charles remained firmly Protestant, he was personally drawn towards a consciously "High Church" Anglicanism. This affected his appointments to Anglican bishoprics, in particular the appointment of William Laud as Archbishop of Canterbury. How many Catholics and Puritans there were is still open to debate.
Religious conflict between Charles and other "High" Anglicans and Calvinists – at this stage mostly still within the Church of England (the Puritans) – formed a strand of the anti-monarchical leanings of the troubled politics of the period. The religious tensions between a court with "Papist" elements and a Parliament in which the Puritans were strong was one of the major factors behind the English Civil War, in which almost all Catholics supported the King. The victory of the Parliamentarians meant a strongly Protestant and anti-Catholic (and, incidentally, anti-Anglican) regime under Oliver Cromwell.
The restoration of the monarchy under Charles II (1660–85) also saw the restoration of a Catholic-influenced court like his father's. However, although Charles himself had Catholic leanings, he was first and foremost a pragmatist and realised the vast majority of public opinion in England was strongly anti-Catholic, so he agreed to laws such as the Test Act requiring any appointee to any public office or member of Parliament to deny Catholic beliefs such as transubstantiation. As far as possible, however, he maintained tacit tolerance. Like his father, he married a Catholic, Catherine of Braganza. (He would become Catholic himself on his deathbed.)
Charles' brother and heir James, Duke of York (later James II), converted to Catholicism in 1668–1669. When Titus Oates in 1678 alleged a (totally imaginary) "Popish Plot" to assassinate Charles and put James in his place, he unleashed a wave of parliamentary and public hysteria which led to anti-Catholic purges, and another wave of sectarian persecution, which Charles was either unable or unwilling to prevent. Throughout the early 1680s the Whig element in Parliament attempted to remove James as successor to the throne. Their failure saw James become, in 1685, Britain's first openly Catholic monarch since Mary I (and last to date). He promised religious toleration for Catholic and Protestants on an equal footing, but it is in doubt whether he did this to gain support from Dissenters or whether he was truly committed to tolerance (contemporary Catholic regimes in Spain and Italy, for example, were hardly tolerant of Protestantism
Catholic Church in England and Wales