On a world-historical scale, I guess the Luso-Chinese agreement was the biggest event of 1554 CE (see more below.) But in England there was more drama from the Real Housewives of the House of Tudor and in the Americas various conquistadorings continued apace…

The bullet-points:

•  In 1554, a Portuguese group headed by Leonel de Sousa, and the authorities of Guangzhou headed by the Provincial Admiral (海道副使; haitao in European sources) Wang Bo (汪柏), reached an agreement that allowed for the legalization of Portuguese trade in China by paying taxes. Till then, the network of Portuguese merchant-adventurers active in the East Indies had been forbidden to trade in or with China since 1522. (The Chinese described them as “folangji”, their variant of the word “ferengi” or “ferenji”– “Franks”– that Arab mariners had brought with them along the Indian ocean’s trading routes several centuries earlier.) In 1554, Wang Bo seems to have insisted the Portuguese pay a rate of 20%. De Sousa didn’t want to go higher than 10%. Finally, the parties agreed the Portuguese would pay 20%– but on only half of any shipload. It is not clear if Wang Bo had totally informed the central authorities in Peking of the terms of his deal. In 1557, the Chinese would allowed De Sousa to establish a warehouse on the Macao Peninsula… which then remained under Portuguese control until (I think) the 1990s. The image above is a 1639 map of Macau.
• In England, meanwhile, the late-30s queen, Mary I, speedily sought a spouse so she could have heirs. Her choice was… Philip, the son and heir of Spain’s King Charles. (Back when she was six, she had been betrothed to Charles himself– a her first cousin– though Charles broke it off. ) English-WP tells us “To elevate his son to Mary’s rank, Emperor Charles V ceded to Philip the crown of Naples as well as his claim to the Kingdom of Jerusalem. Mary thus became Queen of Naples and titular Queen of Jerusalem upon marriage.^[96] Their wedding at Winchester Cathedral on 25 July 1554 took place just two days after their first meeting.^[97] Philip could not speak English, and so they spoke a mixture of Spanish, French, and Latin.” This marriage was a real coup for the Habsburgs, who doubtless envisioned adding England permanently to their portfolio. Philip was already married to somebody else which should have been a problem but apparently was not.
• When Mary’s marriage plans were announced, it caused great concern to a military-minded member of parliament, Thomas Wyatt, who had not been reassured by what he had learned, during an earlier trip to Spain, about the Spanish Inquisition. Wyatt gathered 4,000 fighters and launched a rebellion, apparently asking for help from France (which never came.) Troops loyal to Mary were able to snuff the rebellion out speedily. Wyatt was sentenced to death. English-WP says: “After Wyatt was beheaded, his body was further punished… His head, before it was stolen on 17 April, was hung from a gallows. His limbs were then circulated among towns and also hung up.”
• Mary suspected that her 22-year-old (and Protestant) sister Elizabeth might have been involved in Wyatt’s Rebellion. She imprisoned Elizabeth in the Tower of London and then sent her to be held under house arrest for a year in Woodstock, about 70 miles away.
• In January 1554, Portuguese Jesuits in Brazil established the Colégio de São Paulo de Piratininga on top of a steep hill between the Anhangabaú and Tamanduateí rivers. They first built a small structure of rammed earth, made by American Indian workers in their traditional style. The site was separated from the coast by the Serra do Mar mountain range, called by the Indians “Serra Paranapiacaba”.  The village of São Paulo dos Campos de Piratininga grew up around the Colégio. In 1822, when Brazil became independent of Portugal, its first “Emperor” designated São Paolo its capital…
• 1554 saw the death of a remarkable figure in Iberian/Mediterranean history: Leo Africanus, who had been born “Hasan ibn Muhammad” in Granada in around 1494. Soon after his birth, his family moved to Fez. Smart move! Young Hasan, we learn from English-WP, “studied at the University of al-Qarawiyyin. As a young man he accompanied an uncle on a diplomatic mission, reaching as far as the city of Timbuktu (c. 1510), then part of the Songhai Empire. In 1517 when returning from a diplomatic mission to Constantinople on behalf of the Sultan of Fez Muhammad II he found himself in the port of Rosetta during the Ottoman conquest of Egypt. He continued with his journey through Cairo and Aswan and across the Red Sea to Arabia, where he probably performed a pilgrimage to Mecca. On his way back to Tunis in 1518 he was captured by Spanish corsairs… and imprisoned on the island of Rhodes, the headquarters of the Knights Hospitaller. The usual fate of unransomed Muslim captives was slavery in Christian galleys, but when his captors realized his intelligence and importance, he was moved to the Castel Sant’Angelo in Rome and presented to Pope Leo X. He was soon freed and given a pension to persuade him to stay. He was baptized in the Basilica of Saint Peter’s in 1520. He took the Latin name Johannes Leo de Medicis (Giovanni Leone in Italian)… ” Anyway, the resilient and smart Leo/Hasan drew on his travels and adventures to write Della descrittione dell’Africa et delle cose notabili che ivi sono, which was first published in Venice, in Italian, in 1550. It was published in Antwerp, in French, in 1556, and in London, in English, in 1600. We could think of him as a quintessential “native informant”?