Henry III of Castile, recognizing the looming threat of the Ottoman Empire, sought to strengthen his kingdom's position through diplomacy. In May 1403, he sent Ruy González de Clavijo, a prominent Castilian diplomat and traveler, to Timur, the powerful Central Asian conqueror and ruler known for his expansive empire stretching across Persia and beyond. The intent of this mission was to explore the possibility of a military alliance between Castile and Timur, thus countering the Ottomans' growing power and influence in Europe.

Clavijo's journey was no small feat. It required traversing through treacherous routes, foreign lands, and various courts, where he had to navigate complex political landscapes. His travels took him deep into the heart of Timur's realm, ultimately leading him to the magnificent city of Samarkand. There, he was received in a court famed for its splendor and sophistication, which stood in contrast to the European courts of the time. These interactions allowed Clavijo not only to seek a military alliance but also to observe and record the rich culture and customs of Timur's empire, which he later documented in his works.

The results of this diplomatic mission were significant in that they highlighted the international dynamics of the period. Although the alliance did not materialize as hoped, Clavijo's mission fostered greater awareness and understanding between disparate cultures. Additionally, it marked an important moment in the medieval worldview, as distant kingdoms began contemplating cooperative defenses against mutual threats. With the Ottoman Empire operating on the fringes of Castile's reach, such diplomacy underscored the complexities of maintaining territorial and political sovereignty during tumultuous times.