Papal bull in the context of "Gregorian Calendar"

The Gregorian calendar is the calendar used in most parts of the world. It went into effect in October 1582 following the papal bull Inter gravissimas issued by Pope Gregory XIII, which introduced it as a modification of, and replacement for, the Julian calendar. The principal change was to space leap years slightly differently to make the average calendar year 365.2425 days long rather than the Julian calendar's 365.25 days, thus more closely approximating the 365.2422-day "tropical" or "solar" year that is determined by the Earth's revolution around the Sun.

The rule for leap years is that every year divisible by four is a leap year, except for years that are divisible by 100, except in turn for years also divisible by 400. For example, 1800 and 1900 were not leap years, but 1600 and 2000 were leap years.

A canonical coronation (Latin: Coronatio Canonica) is a pious institutional act of the pope, duly expressed in a formal decree of a papal bull, in which the pope bestows the pontifical right to impose an ornamental crown, a diadem or an aureole to an image of Christ, Mary or Joseph that is widely venerated in a particular diocese or locality. The act was later regulated to Marian images only, through the De coronatione imaginum B.V. Mariae that was issued on 25 March 1973.

The formal act is generally carried out by a representing proxy of the pope, via the designated apostolic nuncio to a country or kingdom, or at times a lesser papal legate, or on rare occasions by the pope himself, by ceremonially attaching a crown, tiara, or stellar halo to the devotional image or statue.

Manifestis Probatum (Latin for 'Manifestly proven') is a papal bull and the founding document of Portugal. On 23 May 1179 Pope Alexander III promulgated the bull. The bull officially recognized the independence of Portugal from Leon by confirming the Kingdom of Portugal to the now-recognized king Afonso Henriques and his successors. The bull is, therefore, the single most important written document from Portugal's independence process.

The Papacy did not recognize the legitimacy of Afonso's adoption of the royal title in 1139, and continued to regard him as a vassal of the kingdom of León. On December 13, 1143, Afonso wrote Pope Innocent II the letter Claves Regni (Latin for 'Keys of the Kingdom'), declaring his decision to enfeoff Portugal to the Holy See and asking for protection against any interference in Portugal's territory. On May 1, 1144, Pope Lucius II replied by letter Devotionen Tuam (Latin for 'Your Devotion') and stated that he recognized Afonso's devotion, but still referred to Portugal as a land instead of a kingdom, and to Afonso as duke instead of a king.

Pope Gregory IX (Latin: Gregorius IX; born Ugolino di Conti; 1145 – 22 August 1241) was head of the Catholic Church and the ruler of the Papal States from 19 March 1227 until his death in 1241. He is known for issuing the Decretales and instituting the Papal Inquisition, in response to the failures of the episcopal inquisitions established during the time of Pope Lucius III, by means of the papal bull Ad abolendam, issued in 1184.

He worked initially as a cardinal, and after becoming the successor of Honorius III, he fully inherited the traditions of Gregory VII and of his own cousin Innocent III, and zealously continued their policy of papal supremacy.

The Crusading movement was a major religious, political and military endeavour of the Middle Ages—began in 1095 when Pope Urban II, at the Council of Clermont, proclaimed the First Crusade to liberate Eastern Christians from Muslim rule. He framed it as a form of penitential pilgrimage, offering spiritual rewards. By then, papal authority in Western Christendom had grown through church reforms, and tensions with secular rulers encouraged the notion of holy war—combining classical just war theory, biblical precedents, and Augustine's teachings on legitimate violence. Armed pilgrimage aligned with the era's Christocentric and militant Catholicism, sparking widespread enthusiasm. Western expansion was further enabled by economic growth, the decline of older Mediterranean powers, and Muslim disunity. These factors allowed crusaders to seize territory and found four Crusader states. Their defence inspired successive Crusades, and the papacy extended spiritual privileges to campaigns against other targets—Muslims in Iberia, pagans in the Baltic, and other opponents of papal authority.

The Crusades fostered distinctive institutions and ideologies, having a great impact on medieval Europe and the Mediterranean. Though aimed primarily at the warrior elite through appeals to chivalric ideals, they depended on broad support from clergy, townspeople, and peasants. Women, despite being discouraged, were involved as participants, proxies for absent crusaders, or victims. Although many crusaders were motivated by indulgences (remission of sins), material gain also played a part. Crusades were typically initiated through papal bulls, with participants pledging to join by "taking the cross"—sewing a cross onto their garments. Failure to fulfil vows could result in excommunication. Periodic waves of zeal produced unsanctioned "popular crusades".

The discovery doctrine, or doctrine of discovery, is a disputed interpretation of international law during the Age of Discovery, introduced into United States municipal law by the US Supreme Court Justice John Marshall in Johnson v. McIntosh (1823). In Marshall's formulation of the doctrine, discovery of territory previously unknown to Europeans gave the discovering nation title to that territory against all other European nations, and this title could be perfected by possession. A number of legal scholars have criticized Marshall's interpretation of the relevant international law. In recent decades, advocates for Indigenous rights have campaigned against the doctrine, which purportedly stemmed from some Papal bulls. In 2023, the Roman Curia of the Vatican formally repudiated the doctrine.

The Treaty of Tordesillas, signed in Tordesillas, Spain, on 7 June 1494, and ratified in Setúbal, Portugal, divided the newly discovered lands outside Europe between the Kingdom of Portugal and the Crown of Castile, along a meridian 370 leagues or 2,100 kilometres (1,300 mi) west of the Cape Verde islands, off the west coast of Africa. That line of demarcation was about halfway between Cape Verde (already Portuguese) and the islands visited by Christopher Columbus on his first voyage (claimed for Castile and León), named in the treaty as Cipangu and Antillia (Cuba and Hispaniola).

The lands to the east would belong to Portugal and the lands to the west to Castile, modifying an earlier bull by Pope Alexander VI. The treaty was created on 7 June 1494, then ratified by Spain on 2 July 1494, by Portugal on 5 September 1494, and by Pope Julius II on 24 January 1506. The other side of the world was divided a few decades later by the Treaty of Zaragoza, signed on 22 April 1529, which specified the antimeridian to the line of demarcation specified in the Treaty of Tordesillas. Portugal and Spain largely respected the treaties, while the Indigenous peoples of the Americas did not acknowledge them.

The University of Glasgow (abbreviated as Glas. in post-nominals; Scottish Gaelic: Oilthigh Ghlaschu) is a public research university in Glasgow, Scotland. Founded by papal bull in 1451 [O.S. 1450], it is the fourth-oldest university in the English-speaking world and one of Scotland's four ancient universities. Along with the universities of St Andrews, Aberdeen, and Edinburgh, the university was part of the Scottish Enlightenment during the 18th century. Glasgow is the second largest university in Scotland by total enrolment and 9th-largest in the United Kingdom.

In common with universities of the pre-modern era, Glasgow originally educated students primarily from wealthy backgrounds; however, it became a pioneer in British higher education in the 19th century by also providing for the needs of students from the growing urban and commercial middle class. Glasgow University served all of these students by preparing them for professions: law, medicine, civil service, teaching, and the church. It also trained smaller but growing numbers for careers in science and engineering.

Quo Primum Tempore (English: From the beginning whence) is the incipit of an Apostolic Constitution in the form of a Papal bull issued by Pope Pius V on 14 July 1570. This Pontifical decree promulgated the Roman Missal and made its use obligatory throughout the Latin Church of the Catholic Church, except where there existed a different Catholic Mass liturgy of the Latin Church of at least two hundred years prior and standing.