Just Close Your Eyes and Think of France
With the stroke of a pen Mad King Charles sells out France, disinherits his own son and pimps out his daughter, Catherine, as he names King Henry the 5th of England as heir to the throne of France and gives Henry the hand of his daughter in marriage. Since Mad King Charles is in fact INSANE, the Treaty of Troyes also makes King Henry the royal regent, handing him control of a large portion of France. The rest is nominally controlled by his ally, Philip the Good, the Duke of Burgundy. Things are really going Henry's way. Catherine will even give birth to an heir! Who could possibly save France now? Joan of Arc is only 8 years old so the burden falls on the slender shoulders of the former heir apparent of France, Charles the 7th.      
Tamerlane's Grandson is a Scientist
Ulugh Beg [OO-loog BEG] has founded a university in Samarkand in present day Uzbekistan. Ulugh Beg [OO-loog BEG] is the grandson of Tamerlane and the one of the few notable scientists amongst the Mongols. (A few have shown up amongst the Persians.) He will set up one of the best astronomical observatories of his time and he will create new star maps. A new star map has not been worked out since the time of Ptolemy [TOLL-uh-mee] and Hipparchus [hih-PAR-kus] around 130 BCE. His writings are in Arabic and Persian so he will remain unknown to the people of Europe. The Mongols don't want to be astronomers so like his grandfather before him, his dream will die with him. He will be murdered by his own son in 1449.  
The Two Capitals of China
With the completion of the palace complex in the Forbidden City, and the repair of the Great Canal the Yongle Emperor has moved the capital of China north to Beijing. He will call it the "Northern Capital" and Nanking will be the southern capital, but the handwriting is on the wall. The transition to the north will be complete by 1450. Construction of the Heavenly Temple has begun and when it is complete, it will become tradition that the Emperor will leave the Forbidden City and make a sacrifice at the Heavenly Temple and then return.      
Tomás de Torquemada is Born
The infamous Torquemada is born. He will become the first Grand Inquisitor of Spain. The world shudders.
This Year in Wikipedia
Year 1420, Wikipedia.
- Previté-Orton, Charles William. The Shorter Cambridge Medieval History, Volume 1, The Later Roman Empire to the Twelfth Century. Cambridge University Press. 1966. p. 979. (BOOK) Quote: "They had possession of the king, the queen, and their daughter Catherine, and on 21 May 1420 they concluded the Treaty of Troyes with Henry 'the Conqueror'. Henry V was recognized as heir to the French throne, and married Charles VI's daughter Catherine. Meantime he was to rule his conquests and share control of Charles with Philip of Burgundy. States General, university, and Paris all submitted."
- Catherine of Valois - Wikipedia, 2014 [last update]
- Grace Dieu (ship) - Wikipedia, 2014 [last update]
- Treaty of Troyes - Wikipedia, 2014 [last update]
- Charles VI of France (Charles the Mad) - Wikipedia, 2014 [last update]
- Charles VII of France (Charles the Well-Served) - Wikipedia, 2014 [last update]
- Hamid Karzai - Wikipedia, 2014 [last update]
- Bourges - Wikipedia, 2014 [last update]
- Asimov, Isaac. Asimov's Biographical Encyclopedia of Science and Technology. Garden City, New York: Doubleday. 1982. ISBN 0385177712. pp. 33-35, 42-43, 65-66. (BOOK) quote: "He (Hipparchus) set up his observatory at Rhodes, an island in the southeastern Aegean, and invented many of the instruments used in naked-eye astronomy for the next seventeen centuries."
- Gernet, Jacques. (translated by Foster, J. R. and Hartman, Charles) A History of Chinese Civilization. Cambridge University Press. 1996. p. 382. (BOOK) quote: "The Mongols instituted in Peking a Moslem observatory (hui-hui ssu-t'ien fat'), in imitation of which the first Ming emperor was to create in Nanking, in the very first year (1368) of his reign, a Moslem astronomical office (hui-hui ssu-t'ien chien)."
- Gernet, Jacques. (translated by Foster, J. R. and Hartman, Charles) A History of Chinese Civilization. Cambridge University Press. 1996. pp. 408-409. (BOOK) quote: "In 1421 Peking was raised to the rank of main capital, whereas until then Nanking had served as the seat of the central government and of the court. But the transfer, made possible by the restoration of the Grand Canal between 1411 and 1415, was carried out gradually, with part of the government service remaining in Nanking, and it was not completed until about 1450."
- Gernet, Jacques. (translated by Foster, J. R. and Hartman, Charles) A History of Chinese Civilization. Cambridge University Press. 1996. p. 408. (BOOK)
- Grand Canal (China): Ming Dynasty Restoration - Wikipedia, 2014 [last update]
- Beijing - Wikipedia, 2014 [last update]
- Temple of Heaven - Wikipedia, 2014 [last update]
- Yongle Emperor - Wikipedia, 2014 [last update]
- Forbidden City - Wikipedia, 2014 [last update]
- FORBIDDEN CITY- The Great Within (Full Documentary) - YouTube, youtube.com, 2014 [last update] Description from YouTube: In 1995 Francis Gerard produced FORBIDDEN CITY, The Great Within - a dramatised documentary. The hour long film was a behind the scenes history of the great Imperial Palace in Beijing from which the Ming and Qing dynasty ruled China for over 500 years. The film was produced by the Discovery Channel.
- Alex Shrugged Notes: My remarks regarding eunuchs comes from my general reading of history. In other words, I remember reading it somewhere and I remember it well but I can't remember the exact citation.