Alfonso X of Castile vs Li Chen

Alfonso X commissioned the Alfonsine Tables, a set of astronomical tables based on Ptolemaic models. These tables were used by European astronomers for centuries and became a standard reference in medieval science.

Alfonso X of Castile was elected King of Germany by a faction of prince-electors, opposing Richard of Cornwall. This election was part of the Great Interregnum, with Alfonso receiving support from the Hohenstaufen loyalists and the Papacy.

Alfonso X never traveled to Germany to assert his claim to the throne. His absence weakened his authority, and he was unable to secure effective control over the German kingdom, leaving the title contested.

Alfonso X formally renounced his claim to the German throne in favor of Rudolf of Habsburg. This renunciation ended the Great Interregnum and allowed Rudolf to be recognized as the legitimate king of Germany.

Li Chen ascended the throne after the death of his nephew, Li Yan. He immediately reversed the anti-Buddhist policies and began a series of reforms to restore central authority. He appointed capable chancellors and reduced the power of eunuchs.

Li Chen reformed the state salt monopoly to increase revenue and reduce corruption. He lowered salt prices to curb smuggling and improved the efficiency of the monopoly system, which became a major source of Tang fiscal stability.

Li Chen's forces launched a campaign to recapture the Hexi Corridor from the Tibetan Empire. Tang armies achieved several victories, regaining control of key cities and restoring Chinese authority over the Silk Road route.

Li Chen died in 859 after a reign that briefly revived Tang fortunes. He was posthumously called the 'Little Taizong' for his capable rule. His death marked the end of the last period of Tang stability before the dynasty's final decline.