Jani Beg vs Michael I Rangabe

Jani Beg besieged the Genoese trading colony of Caffa in Crimea. During the siege, the Mongol army reportedly catapulted plague-infected corpses into the city, contributing to the spread of the Black Death to Europe. The siege was eventually lifted.

Jani Beg continued the Golden Horde's conflict with the Ilkhanate, launching campaigns into the Caucasus. The war weakened both states and contributed to the decline of the Ilkhanate, but also drained the Golden Horde's resources.

Jani Beg led the Golden Horde army in the conquest of Tabriz, the capital of the Chobanid dynasty in Persia. The city was sacked, and the Golden Horde reached its greatest territorial extent, controlling the Caucasus and parts of Persia.

Michael I Rangabe was proclaimed emperor after the death of Nikephoros I in the Battle of Pliska. He was a son-in-law of Nikephoros and a member of the court. His reign was short and marked by military setbacks.

Michael I reversed the iconoclast policies of his predecessor and restored the veneration of icons. He also restored the rights of monks and monasteries that had been persecuted under Constantine V. This aligned him with the iconophile faction.

Michael I led a Byzantine army against the Bulgars under Khan Krum at Versinikia. The battle ended in a decisive Bulgarian victory. The Byzantine army fled, and Michael's reputation was severely damaged.

After the defeat at Versinikia, Michael I abdicated the throne and became a monk under the name Athanasios. He spent the remainder of his life in a monastery, avoiding further involvement in politics. He died in 844.