During the archaeological works, floor mosaics were found in the church underground, dating back to the times of the Republic, from the III century BC. and testifying to the fact that once this  was the location of an exclusive district of villas and gardens. A large hall with an apse (ecclesiae Apostolorum), which was most likely intended for Christian ceremonies, was built on top of residential buildings dating back to the III and IV centuries B.C. It was used in the construction of another church (mid-V century), during the times of Pope Sixtus III, initially dedicated to two Roman martyrs - Peter and Paul. The founder of the building was Licinia Eudoxia, wife of the then Emperor of the Western Empire - Valentinian III. And here the legend begins. Apparently, the empress possessed exceptional relics - the chains of St. Peter, which her mother (Aelia Eudoxia) acquired during her pilgrimage to Jerusalem. According to tradition the apostle was shackled in them in the year 44 A.D., while in prison. Licinia Eudoxia, was in turn to give them to the successor of Sixtus V, Pope Leo I. And this is where the second part of the legend begins. It turns out that, different chains of St. Peter, the ones from the Roman prison (Mamertinum), which were in the possession of the aforementioned Pope Leo I, in a miraculous way combined with the chains from Jerusalem. Information from the V century confirms that, at that time the shackles thought of as holy, were already  located in the church in question and they were the ones from which in the VI century the church took its name – “St. Peter in Chains” (in Vincoli). They also became the main attraction of pilgrim visits to this place. The church itself, since the beginning of its existence enjoyed great esteem. It belonged to a group of the so-called station churches in which the tradition of the Lent stations was cultivated, meaning those connected with a procession of services, celebrated on each day of Lent in a different church in Rome. Inside this very church in 533, John II was elected pope, similarly to Gregory VII five hundered years later in 1073.

Today, standing inside the basilica we can still notice the early-Christian structure of the empress. We are reminded of it by the broad main nave, opening up with a row of Doric columns onto two narrow side naves, as well as a broad apse in the altar part.

In the following centuries the church fell into ruin, especially during the Middle Ages, when the popes stayed in Avignon (the Avignon Papacy). It underwent thorough modernization thanks to its titular cardinal, Nicholas of Cusa, who not only saved the church from collapsing, but after his death left a significant sum of money, which subsequent caretakers of this building used for its modernization. This task fell to two cardinals from the della Rovere family – Francesco, who became Pope Sixtus IV in 1471, and his nephew Giuliano, who also attained the papal tiara in 1503, as Julius II. As a reminder: the former is responsible for erecting the Sistine Chapel in the palace complex on the Vatican, the latter – its decoration with frescoes of the divine Michelangelo.

It is time to visit the church. Sightseeing generally begins with the work of Michelangelo found in the right transept. We are greeted with a monumental funerary monument of Pope Julius II. It was to be, for the still young artist, his greatest work, a structure which would take our breath away, and overshadow everything that had been created in marble until then. It constituted a true artistic challenge, one of which the ambitious sculptor dreamed. However, it turned out to be one of his life’s biggest disappointments, a struggle, a haunting and his greatest artistic failure. When Michelangelo began his work, the monument had forty figures, several stories and was more reminiscent of a mausoleum than a tomb. However, other ideas and commissions did not allow Pope Julius II to make good on his intention – he became terrified of the enormous costs, the unearthly vision of the artist, but also perhaps the splendor which was not fit for a pope – all these factors caused the design to be discarded. It was picked up again after the pope’s death but in a much lesser form, however Michelangelo’s other tasks did not allow him to focus on such a great undertaking. Finally in 1545, therefore, forty years after the initial commission, with aid from the artist’s apprentices, the sixth in a row design was completed, which in relation to the initial assumptions was just a pathetic compromise. From the grand, initial concept the only thing left in Rome was the imposing and admirable Moses, as well as the figures sculpted by Michelangelo himself of Leah and Rachel (the symbols of active and contemplative life) and also – recently recognized as his work – figure of the lying Pope Julius II. This monument was first destined for the Basilica of San Pietro in Vaticano, of which Julius II was the principal initiator and founder and where in the catacombs he was eventually laid to rest. However, the only thing that commemorates his name there is an epitaph.

In the Basilica of St. Peter in Chains, immediately next to the monument, on the left, there is a generally overlooked altar with a painting of St. Margaret, completed by the well-known and valued painter of the Baroque – Guercino. Turning our back to Michelangelo’s masterpiece and directing our gaze below the level of the floor, we will notice the principal relic of the church – the chains of St. Peter, built into the confessio and covered with a monumental XIX-century baldachin. When we lift our eyes and direct them towards the apse, we will notice a painting story concerning the aforementioned chains. On the left, we are led into a prison, where in a miraculous way, taking advantage of the inattention of the sleeping guards, an angel sets Peter free. In the center, we will see Empress Aelia Eudoxia, who during her trip to Jerusalem, receives the apostle’s chains from the local bishop, Juvenal. On the right, we see her daughter giving the shackles to Pope Leo I. The author of these frescoes in a representative of Mannerism, Jacopo Coppi (1577).

Directing our gaze even higher, we notice a composition made up of numerous scenes with a theme of the miracle of The Crucifix from Beirut. It is a sort of morality play meant to show the superiority of Catholicism over Judaism. Summarizing the colorful story – it is a tale of a crucifix found and desecrated by Jews in Beirut during the reign of Constantine IV, in the house of a Christian residing there. The blood, which suddenly flowed from the cross, aroused not only their amazement, but – as it turned out – it miraculously healed all those who found themselves nearby. The Jews carried the cross to the local bishop, converted to Christianity, allowed themselves to be baptized, while they converted their synagogue into a church, dedicating it to Jesus Christ.

Apart from Michelangelo’s monument and eye-catching apse frescoes, the church contains several other works worthy of attention.

In the right nave (looking from the altar)

•     An imposing Baroque tombstone of Cardinal Mariano Pietro Vecchiarelli (1639). Here we are dealing with popular in the art of Baroque, a sort of danse macabre performed by two skeletons, which are flanking a tondo with the portrait of the deceased. They are to remind us of the fleetingness and miserableness of human life and all human affairs in face of impending death. The floor, directly in front of the monument also merits attention, made of marble tiles (family coat of arms) in the pietra dura
•     The Byzantine mosaic right next to it, from the VII century depicts St. Sebastian. It was probably brought here as an ex voto in thanks for the end of a plague which ravaged the city in 680. Most likely it was a part of an altar which was taken apart in the XVI, devoted to this saint – liberator from epidemics.

•     The next tombstone belongs to the nephew and nepot of Pope Clement VIII, and at the same time the patron of the writer Torquato Tasso – Cardinal Cinzio Passeri Aldobrandini (1707) and is a kind of quintessence of funerary art of late Baroque. Francesco Carlo Bizzaccheri created the architectural arrangements for it, while the active in Rome, outstanding French sculptor Pierre Le Gros, with finesse, but also a certain dose of humor depicted the personification of Death. With sunken eyes sockets, the grim reaper is holding a scythe and an hourglass in its upper limbs, while the lower limbs appearing from behind the sarcophagus create a dance routine.
•     Moving on, we come across an altar with the painting of a mannerist, very active in Rome, the author of numerous painting decorations in the city – Pomarancio (Cristoforo Roncalli), depicting the scene of The Entombment
•     Nearest the exit is a tombstone made in a completely different style, of the aforementioned caretaker of the basilica – Cardinal Nicholas of Cusa. The work, this time of early Renaissance, was created in 1464 and depicts St. Peter, the cardinal and an angel (the liberator of the apostle from prison) and is attributed to the outstanding artist of that time, Andrea Bregno. Cardinal Cusa (or more appropriately Nicolaus Krebs), from the area of Trier, was the titular cardinal of the church, but apart from that a philosopher, humanist and scientist who preached quite bold theories about the Solar System.
•     Right at the exit is an interesting tombstone of two significant artists, who while they are originally from Florence, were connected to Rome due to prestigious work they had done there – Antonio and Piero Pollaiuolo (1498). The elder was a sculptor and a goldsmith, the younger – a sculptor but above all a skilled painter. They are responsible for the funerary monuments found in the Vatican Basilica of popes Sixtus IV and Innocent VIII. Above the artists’ heads there is a fresco depicting Penitential Procession During the Plague of 1476. A work of an unknown artist crated around the year 1500.

In the old anti-sacristy, which today houses a souvenir shop, on one of the walls is a painting of the outstanding Baroque painter Domenichino depicting The Liberation of St. Peter (1604.

Before leaving the church, it is worth taking a look at the vault of the main nave. There we will notice a fresco from the beginning of the XVIII century depicting the miraculous power of the chains of St. Peter, this time in an almost exorcist act. Its author is the late-Baroque painter Giovanni Battista Parodi. The subject of this interesting painting is the exorcism of a demon from the graf from the court of the German Emperor Otto I, who came to Rome. The act is performed by Pope John XII.

Before we definitely bid farewell to this beautiful church, we should direct our steps to the buildings of the former monastery found nearby. In the XIX and XX centuries it was converted into the Faculty of Civil Engineering and Engineering, however the courtyard was preserved (entry through the main doors of the school). Its central point is occupied by a seventeenth-century fountain and a well from the beginning of the XVI century, with a well visible coats of arms (oak) of two popes from the della Rovere family – Sixtus IV and Julius II. In the complex of the Basilica of San Pietro in Vincoli, they were the ones who financed, among others, the Renaissance entrance portico with five arcades and these very cloisters. Their designer was the Florentine architect Giuliano da Sangallo, the brother of Antonio da Sangallo.