Mahmud I of Great Seljuk vs Otto IV

Following the death of his father Malik Shah I, Mahmud I was proclaimed sultan at age five. His mother Terken Khatun acted as regent, but the succession was contested by his half-brothers Barkiyaruq and others, leading to civil war.

Forces loyal to Mahmud I, led by his mother Terken Khatun and general Kerbogha, fought against Barkiyaruq's army near Al-Ruhaymi in Iraq. Mahmud's forces were defeated, weakening his claim to the sultanate.

Mahmud I died at age seven, likely from illness. His death ended his brief reign and allowed Barkiyaruq to consolidate power as the sole Seljuk sultan, though the empire remained divided by ongoing succession conflicts.

Otto IV was elected King of Germany in June 1198 by Welf supporters, opposing Philip of Swabia. His election sparked a civil war with the Hohenstaufen faction that lasted a decade.

Pope Innocent III crowned Otto IV Holy Roman Emperor in Rome on October 4, 1209, after Otto promised to respect papal territories. The coronation ended the civil war and made Otto the sole ruler.

Pope Innocent III excommunicated Otto IV in 1210 after Otto invaded the Kingdom of Sicily, violating his promises. The exclamation led to the election of Frederick II as rival king and Otto's decline.

Otto IV was decisively defeated by King Philip II of France at the Battle of Bouvines on July 27, 1214. This defeat ended Otto's imperial ambitions and led to his loss of the German throne to Frederick II.