Galileo Galilei arrives in Rome for his trial before the Inquisition.

Galileo di Vincenzo Bonaiuti de' Galilei, commonly referred to as Galileo Galilei or mononymously as Galileo, was an Italian astronomer, physicist, and engineer, sometimes described as a polymath. He was born in the city of Pisa, then part of the Duchy of Florence. Galileo has been called the father of observational astronomy, modern-era classical physics, the scientific method, and modern science.

Rome is the capital city and most populated comune (municipality) of Italy. It is also the administrative centre of the Lazio region and of the Metropolitan City of Rome. A special comune named Roma Capitale with 2,746,984 residents in 1,287.36 km² (497.1 sq mi), Rome is the third most populous city in the European Union by population within city limits. The Metropolitan City of Rome Capital, with a population of 4,223,885 residents, is the most populous metropolitan city in Italy. Its metropolitan area is the third-most populous within Italy. Rome is located in the central-western portion of the Italian Peninsula, within Lazio (Latium), along the shores of the Tiber Valley. Vatican City is an independent country inside the city boundaries of Rome, the only existing example of a country within a city. Rome is often referred to as the City of Seven Hills due to its geography, and also as the "Eternal City". Rome is generally considered to be one of the cradles of Western civilization and Western Christian culture, and the centre of the Catholic Church.

The Inquisition was a Catholic judicial procedure where the ecclesiastical judges could initiate, investigate and try cases in their jurisdiction. Popularly it became the name for various medieval and reformation-era state-organized tribunals whose aim was to combat heresy, apostasy, blasphemy, witchcraft, and customs considered to be deviant, using this procedure. Violence, isolation, torture or the threat of its application, have been used by the Inquisition to extract confessions and denunciations. Inquisitions with the aim of combatting religious sedition had their start in the 12th-century Kingdom of France, particularly among the Cathars and the Waldensians. The inquisitorial courts from this time until the mid-15th century are together known as the Medieval Inquisition. Other banned groups investigated by medieval inquisitions, which primarily took place in France and Italy, include the Spiritual Franciscans, the Hussites, and the Beguines. Beginning in the 1250s, inquisitors were generally chosen from members of the Dominican Order, replacing the earlier practice of using local clergy as judges.