Pope Alexander VI issues the papal bull Dudum siquidem to the Catholic Monarchs, extending the grant of new lands he made them in Inter caetera.

Inter caetera ('Among other [works]') was a papal bull issued by Pope Alexander VI on the 4 May (quarto nonas maii) 1493, which granted to the Catholic Monarchs King Ferdinand II of Aragon and Queen Isabella I of Castile all lands to the "west and south" of a pole-to-pole line 100 leagues west and south of any of the islands of the Azores or the Cape Verde islands.It remains unclear whether the pope intended a "donation" of sovereignty or an infeudation or investiture. Differing interpretations have been argued since the bull was issued, with some arguing that it was only meant to transform the possession and occupation of land into lawful sovereignty. Others, including the Spanish crown and the conquistadors, interpreted it in the widest possible sense, deducing that it gave Spain full political sovereignty.Inter caetera and its supplement Dudum siquidem (September 1493) are two of the Bulls of Donation. While these bulls purported to settle disputes between Spain and Portugal, they did not address the exploratory and colonial ambitions of other nations, which became more of an issue after the Protestant Reformation.

Pope Alexander VI (Italian: Alessandro VI; born Rodrigo de Borja; Valencian: Roderic Llançol i de Borja [roðeˈɾiɡ ʎanˈsɔl i ðe ˈbɔɾdʒa]; Spanish: Rodrigo Lanzol y de Borja [roˈðɾiɣo lanˈθol i ðe ˈβoɾxa]; 1 January 1431 – 18 August 1503) was head of the Catholic Church and ruler of the Papal States from 11 August 1492 until his death in 1503.

Born into the prominent Borgia family in Xàtiva under the Crown of Aragon (now Spain), Rodrigo studied law at the University of Bologna. He was ordained deacon and made a cardinal in 1456 after the election of his uncle as Pope Callixtus III, and a year later he became vice-chancellor of the Catholic Church. He proceeded to serve in the Curia under the next four popes, acquiring significant influence and wealth in the process. In 1492, Rodrigo was elected pope, taking the name Alexander VI.

Alexander's papal bulls of 1493 confirmed or reconfirmed the rights of the Spanish crown in the New World following the finds of Christopher Columbus in 1492. During the second Italian war, Alexander VI supported his son Cesare Borgia as a condottiero for the French king. The scope of his foreign policy was to gain the most advantageous terms for his family.Alexander is considered one of the most controversial of the Renaissance popes, partly because he acknowledged fathering several children by his mistresses. As a result, his Italianized Valencian surname, Borgia, became a byword for libertinism and nepotism, which are traditionally considered as characterizing his pontificate. On the other hand, two of Alexander's successors, Sixtus V and Urban VIII, described him as one of the most outstanding popes since Saint Peter.