Pope Gregory IX in the context of "Saint Francis of Assisi"

Excommunication is an institutional act of religious censure used to deprive, suspend, or limit membership in a religious community or to restrict certain rights within it, in particular those of being in communion with other members of the congregation, and of receiving the sacraments.

It is practiced by all of the ancient churches (such as the Catholic Church, Oriental Orthodox churches and the Eastern Orthodox churches) as well as by other Christian denominations; however, it is also used more generally to refer to similar types of institutional religious exclusionary practices and shunning among other religious groups. The Amish have also been known to excommunicate members that were either seen or known for breaking rules, or questioning the church, a practice known as shunning. Jehovah's Witnesses use the term disfellowship to refer to their form of excommunication.

Turku (/ˈtʊərkuː/ TOOR-koo; Finnish: [ˈturku] ; Swedish: Åbo, Finland Swedish: [ˈoːbu] ) is a city in Finland and the regional capital of Southwest Finland. It is located on the southwestern coast of the country at the mouth of the River Aura. The population of Turku is approximately 207,000, while the metropolitan area has a population of approximately 317,000. It is the 6th–most populous municipality in Finland, and the third–most populous urban area in the country after Helsinki and Tampere.

Turku is Finland's oldest city. It is not known when Turku was granted city status. Pope Gregory IX first mentioned the town of Aboa in his Bulla in 1229, and this year is now used as the founding year of the city. Turku was the most important city in the eastern part (today's Finland) of the Kingdom of Sweden. After the Finnish War, Finland became an autonomous Grand Duchy of the Russian Empire in 1809, and Turku became the capital of the Grand Duchy. However, Turku lost its status as capital only three years later in 1812, when Tsar Alexander I of Russia decided to move the capital to Helsinki. It was only after the last great fire in 1827 that most government institutions were moved to Helsinki along with the Royal Academy of Turku, founded in 1640, which later became the University of Helsinki, thus consolidating Helsinki's position as the new capital. Turku was Finland's most populous city until the late 1840s and remains the regional capital, an important business and cultural centre, and a port.

The Republic of Noli (Italian: Repubblica di Noli; Ligurian: Repubbrica de Nöi) was an Italian maritime republic that was centred on the city of Noli, in Liguria, and existed from 1192 to 1797. The area is now in the province of Savona, Italy. To protect itself from possible attacks and invasions by Savona and Marquisate of Finale, Noli allied in 1202 with the Republic of Genoa in a sort of protectorate, in fact, documents of the time show that the relationship was equal and not one of submission. The alliance allowed the Republic of Noli to have such growing importance that in 1239, a diocese was established there by Pope Gregory IX.

Giovanni di Pietro di Bernardone (c. 1181 – 3 October 1226), known as Francis of Assisi, was an Italian mystic, poet and Catholic friar who founded the religious order of the Franciscans. Inspired to lead a Christian life of poverty, he became a beggar and an itinerant preacher.

One of the most venerated figures in Christianity, Francis was canonized by Pope Gregory IX on 16 July 1228. He is commonly portrayed wearing a brown habit with a rope tied around his waist, featuring three knots symbolizing the evangelical counsels of poverty, chastity, and obedience.

Ferdinand III (Spanish: Fernando; 1199/1201 – 30 May 1252), called the Saint (el Santo), was King of Castile from 1217 and King of León from 1230 as well as King of Galicia from 1231. He was the son of Alfonso IX of León and Berengaria of Castile. Through his second marriage he was also Count of Aumale. Ferdinand III was one of the most successful kings of Castile, securing not only the permanent union of the crowns of Castile and León, but also masterminding the most expansive southward territorial expansion campaign yet in the Guadalquivir Valley, in which Islamic rule was in disarray in the wake of the defeat of the Almohad caliphate at the Battle of Las Navas de Tolosa. His repeated and decisive victories against the Islamic Caliphate earned him the title Athleta Christi, meaning 'Champion of Christ', which was conferred upon him by Pope Gregory IX.

By military and diplomatic efforts, Ferdinand greatly expanded the dominions of Castile by annexing the crown of Guadalquivir river valley in the south of the Iberian Peninsula, establishing the boundaries of the Castilian state for the next two centuries. New territories included important cities such as Baeza, Úbeda, Jaén, Córdoba and Seville, that were subject of Repartimiento, given a new general charter and repopulated in the following years.

The Decretals of Gregory IX (Latin: Decretales Gregorii IX), also collectively called the Liber extra, are a source of medieval Catholic canon law. In 1230, Pope Gregory IX ordered his chaplain and confessor, Raymond of Penyafort, a Dominican, to form a new canonical collection destined to replace the Decretum Gratiani, which was the chief collection of legal writings for the church for over 90 years. It has been said that the pope used these letters to emphasize his power over the Universal Church.

The Sixth Crusade (1228–1229), also known as the Crusade of Frederick II, was (like the other Crusades) a military expedition to recapture Jerusalem and the rest of the Holy Land. It began seven years after the failure of the Fifth Crusade and involved very little actual fighting. The diplomatic maneuvering of the Holy Roman emperor and king of Sicily, Frederick II, resulted in the Kingdom of Jerusalem regaining some control over Jerusalem for much of the ensuing fifteen years as well as over other areas of the Holy Land. Frederick II's negotiations and power-sharing agreement and negotiation with envoys from al-Malik Al-Kamil of Egypt, which led to a shared Christian-Muslim governance situation in Jerusalem, made this Crusade different from the others (and some call it the only successful one). Frederick II carried out his maneuvers in 1228 while under excommunication from the Church by Pope Gregory IX.

Pope Innocent IV (Latin: Innocentius IV; c. 1195 – 7 December 1254), born Sinibaldo Fieschi, was head of the Catholic Church and ruler of the Papal States from 25 June 1243 to his death in 1254.

Fieschi was born in Genoa and studied at the universities of Parma and Bologna. He was considered in his own day and by posterity as a fine canonist. On the strength of this reputation, he was called to the Roman Curia by Pope Honorius III. Pope Gregory IX made him a cardinal and appointed him governor of the Ancona in 1235. Fieschi was elected pope in 1243 and took the name Innocent IV. He inherited an ongoing dispute over lands seized by the Holy Roman Emperor, and the following year he traveled to France to escape imperial plots against him in Rome. He returned to Rome in 1250 after the death of the Emperor Frederick II.