Al-Mutawakkil vs King Hyeonjong of Goryeo

Al-Mutawakkil ended the Mihna, the inquisition that enforced the Mu'tazilite doctrine of the createdness of the Quran. He restored traditionalist orthodoxy and ended the persecution of scholars who opposed the doctrine.

Al-Mutawakkil commissioned the construction of the Great Mosque of Samarra, featuring the famous Malwiya minaret. This mosque was one of the largest in the Islamic world and symbolized Abbasid architectural ambition.

Al-Mutawakkil was assassinated by his Turkish guard in Samarra. The murder was orchestrated by his son al-Muntasir, who succeeded him. This event marked the beginning of the 'Anarchy at Samarra' and the decline of Abbasid power.

The Liao dynasty (Khitan) invaded Goryeo with a large army. King Hyeonjong, advised by General Seo Hui, negotiated a settlement. The Khitan withdrew after Goryeo agreed to end relations with Song China, but the border was not ceded.

Emperor Shengzong of Liao invaded Goryeo after Hyeonjong refused to pay homage. The Khitan captured the capital Gaegyeong. Hyeonjong fled to Naju. The invasion ended with a Khitan withdrawal after a failed siege of a fortress.

Following the Khitan invasions, King Hyeonjong ordered the construction of a massive defensive wall in northern Goryeo. The Cheolli Jangseong (Thousand Li Wall) was built to fortify the border against future invasions from the Liao dynasty.

King Hyeonjong oversaw the compilation and promulgation of a comprehensive legal code, the Goryeo Code. This code systematized laws and administrative regulations, strengthening central governance and legal consistency across the kingdom.

The Liao dynasty launched a third invasion. General Gang Gam-chan led Goryeo forces to a decisive victory at the Battle of Gwiju. The Khitan army was nearly annihilated, ending the Liao invasions and securing Goryeo's independence.