History: Queen Elizabeth I

We're about to date back to the 16th century, when Elizabeth I succeeded to the throne after her stepsister's death. Henry VIII and Anne Boleyn's daughter had always had differences with Queen Mary I as for religious issues. The English Church experienced a thorough change during her reign although her cousin's shadow, Mary Queen of Scots, floated around her (something she could not take).
Here's an excerpt taken from Wikipedia about Queen Elizabeth I:

The reign of Elizabeth restored a sort of order to the realm following the turbulence of the reigns of Edward and Mary when she came to the throne following the death of Mary in 1558. The religious issue which had divided the country since Henry VIII was in a way put to rest by the Elizabethan Religious Settlement, which re-established the Church of England. Much of Elizabeth's success was in balancing the interests of the Puritans and Catholics. She managed to offend neither to a large extent, although she clamped down on Catholics towards the end of her reign as war with Catholic Spain loomed. The war lasted from 1585 - 1603. In 1588, the Spanish Armada was decisively defeated, marking the beginning of England's rise as a naval power. Indecisive skirmishing continued throughout the 1590's, with English privateers pillaging Spanish commerce from America.

The queen ran afoul of her cousin Mary, Queen of Scots, who was a devote Catholic and had been forced to abdicate her throne as a consequence ( Scotland had recently become Protestant ). She fled to England, where Elizabeth immediately had her arrested. She was eventually tried for treason and sentenced to death, being beheaded in February 1587.

Elizabeth died in 1603. Her closest male Protestant relative was the King of Scots, James VI, of the House of Stuart, who became King James I of England in a Union of the Crowns.

to date back = remontarse ( a un tiempo pasado)
stepsister = hermanastra
thorough = completo
realm = reino
to clamp down on = tomar medidas drásticas contra
to loom = telar, avecinarse (en este caso)
skirmish = escaramuza
to flee = huir
treason = traición
to behead = decapitar
relative = pariente