Bergamo has been intermittently under the rule…

Ulugh Beg is a grandson of the great conqueror, Timur (Tamerlane) (1336–1405), and the oldest son of Shah Rukh, both of whom had come from the Turkicized Barlas tribe of Transoxiana (now Uzbekistan).

His mother was a Persian noblewoman named Goharshad.

Ulugh Beg was born in Sultaniyeh in Persia during Timur's invasion.

As a child he had wandered through a substantial part of the Middle East and India as his grandfather expanded his conquests in those areas.

After Timur's death, however, and the accession of Ulugh Beg's father to much of the Timurid Empire, he had settled in Samarkand, which had been Timur's capital.

After Shah Rukh moved the capital to Herat (in modern Afghanistan), sixteen-year-old Ulugh Beg had become his governor in Samarkand in 1409.

In 1411, he had became the sovereign ruler of the whole Mavarannahr khanate (Transoxiana).

The teenaged ruler had set out to turn the city into an intellectual center for the empire.

Between 1417 and 1420, he has built a madrasa ("university" or "institute") on Registan Square in Samarkand (currently in Uzbekistan), and has invited numerous Islamic astronomers and mathematicians to study there.

The madrasa building still survives.

Ulugh Beg's most famous pupil in astronomy is Ali Qushchi (died in 1474).

His own particular interests are concentrated on astronomy, and, in 1428, he built an enormous observatory, called the Gurkhani Zij, similar to Tycho Brahe's later Uraniborg as well as Taqi al-Din's observatory in Istanbul.

Lacking telescopes to work with, he increased his accuracy by increasing the length of his sextant; the so-called Fakhri sextant had a radius of about thirty-six meters (one hundred and eighteen feet) and the optical separability of 180" (seconds of arc).

The small town of Copenhagen, located on the eastern shore of the island of Sjaelland, or Zealand, at the southern end of Oresund (The Sound), the waterway that separates Denmark from Sweden and links the Baltic with the North Sea, began to develop in the twelfth century as a fortified fishing village.

With the establishment of the Kalmar Union (1397–1523) between Denmark, Norway and Sweden, by about 1416 Copenhagen had emerged as the capital of Denmark when Eric of Pomerania moved his seat to Copenhagen Castle the following year, thereby assuring the city’s status as the capital of Denmark.

Eric is at war from 1426 to 1435 with the German Hanseatic League and Holstein.

When the Hanseats and Holsteiners in 1428 attack Copenhagen, Eric leaves the city and his wife, Queen Philippa, manages the defense of the capital, a heroic feat later recounted by Hans Christian Andersen in Godfather's Picture Book (1868).

German Emperor Sigismund, the unity of Western Christendom having been restored in 1417, hopes to lead a new crusade against the Turks.

The campaign that he leads against them in 1427-28, however, ends, like his crusade three decades earlier, with few results.

Hungary-Croatia has lost Dalmatia to Venice between 1420 and 1428.

Venetian is the commercial lingua franca in the Mediterranean at this time, and it heavily influences Dalmatian and to a lesser degree coastal Croatian and Albanian.

Masolino returns from Hungary and works from 1427 to 1431 on the mural cycle for the Chapel of Saint Catherine in San Clemente, in Rome, where the painter’s cool, luminous refinement once again prevails over the intensely emotional work of his collaborator, Masaccio, who dies in Rome in 1428, while still in his late twenties, leaving incomplete his Brancacci Chapel decoration.

Guillaume Dufay, from the evidence of his will, was probably born in Beersel, in the vicinity of Brussels, the illegitimate child of an unknown priest and a woman named Marie Du Fayt.

She moved with her son to Cambrai early in his life, staying with a relative who was a canon of the cathedral there.

His musical gifts were noticed by the cathedral authorities, who evidently gave him a thorough training in music; he studied with Rogier de Hesdin during the summer of 1409, and he was listed as a choirboy in the cathedral from 1409-12.

During those years he studied with Nicolas Malin, and the authorities must have been impressed with the boy's gifts because they gave him his own copy of Villedieu’s Doctrinale in 1411, a highly unusual event for one so young.

In June 1414, aged around sixteen, he had already been given a benefice as chaplain at St. Géry, immediately adjacent to Cambrai.

Later that year, on the evidence of music composed, and a later relationship with the Malatesta court, members of which he met on the trip, he probably went to the Council of Konstanz.

He likely stayed there until 1418, at which time he returned to Cambrai.

From November 1418 to 1420 he was a subdeacon at Cambrai Cathedral.

In 1420 he left Cambrai again, this time going to Italy—first to Rimini and then possibly Pesaro, where he worked for the Malatesta family.

Although no records survive of his employment there, several compositions of his can be dated to this period; they contain references that make a residence in Italy reasonably certain.

There he met the composers Hugo and Arnold de Lantins, who were among the musicians of the Malatesta household.

In 1424 Dufay again returned to Cambrai, this time because of the illness and subsequent death of the relative with whom his mother was staying.

By 1426, however, he had gone back to Italy, this time to Bologna, where he entered the service of Cardinal Louis Aleman, the papal legate.

While in Bologna he has become a deacon, and by 1428 he is a priest.

Cardinal Aleman is driven from Bologna by the rival Canedoli family in 1428, and Dufay also leaves at this time, going to Rome.

Florence, exhausted by its part in the Venetian-Milanese Wars, sues for peace.

With the mediation of the Pope, the peace is signed on April 18, 1428 at Ferrara, under the terms which Venice receives Brescia and part of Cremona.

King Eric's introduction in 1429 of the Sound Dues (Øresundtolden), which will last until 1857, is perhaps his most far-ranging act.

He secures by this act a large stable income for his kingdom that will make it relatively rich and which will make the town of Elsinore flourish.

It shows his interest in Danish trade and naval power, but also permanently challenges the other Baltic powers, especially the Hanseatic cities against which he also fights.

Jean Gerson, former chancellor of the University of Paris, after returning in 1419 from the Tyrol to France,  had gone to Lyon, where his brother was prior of the Celestine monastery.

Although Gerson is retired from active university life, the past decade at Lyon has been a time of great literary productivity.

He has produced a harmony of the gospels (the Monotesseron), works on the poems of the bible climaxing in a massive collection of twelve treatises on the Magnificat (Lk. 1:46-55), a commentary on the Song of Songs, as well as an extensive literary correspondence with members of the Carthusian order and others on mysticism and other issues of spiritual life.

Shortly before his death at sixty-five on July 12, 1429, he produces a tract in support of Joan of Arc.

A large fragment of a mid-first century marble statue of a seated pugilist by the Athenian sculptor Apollonius, the son of Nestor, is found in Rome before 1430.

Known as the Belvedere Torso (and closely related to the bronze statue of a seated boxer now in the Terme Museum, Rome, which is probably by the same sculptor and suggests the statue's original appearance), the Belvedere Torso influences contemporary Italian painters, sculptors, and graphic artists on their various renditions of the male torso.