Abbasid caliph al-Mutawakkil (r. 847–861) and decline of the Abbasid Caliphate. 862: The beginning of the Rurik Dynasty in Rus'. 863: The Chinese author Duan Chengshi describes the slave trade, ivory trade, and ambergris trade of Somalia in East Africa. 862: The Bagratuni Dynasty of Medieval Armenia begins with Ashot I. 863–879: Period of schism between Eastern and Western churches. 864: Christianization of Bulgaria under Boris I 867: Onward revival of the Byzantine Empire under the Macedonian dynasty. 868: Ahmad ibn Tulun breaks away from the Abbasid Caliphate and establishes the independent Tulunid dynasty. 869: An earthquake and tsunami struck Japan's Sanriku coast, killing 1,000 people. 870: Christianization of the Serbs. 870: Prague Castle founded. 871–899: Reign of Alfred the Great, the first king of the English. 872: Iceland settled by Ingolfur Arnarson from Norway. 875–884: Huang Chao leads an unsuccessful rebellion against the Tang Dynasty in China. 878: Battle of Ethandun results in the victory of Alfred the Great over the Danish warlord Guthrum. 885: Arrival of the disciples of Saints Cyril and Methodius, Clement of Ohrid and Naum of Preslav in Bulgaria. Development of the Cyrillic Alphabet. 885: Abbo Cernuus becomes witness to the Siege of Paris by Vikings. 888: The Carolingian Empire declines and falls after the death of Charles the Fat. 893: Council of Preslav - Vladimir-Rasate is dethroned and succeeded as Prince of Bulgaria by Simeon I; the capital is moved from Pliska to Preslav; the Byzantine clergy is expelled and replaced by Bulgarian; Old Bulgarian becomes the official language of the country. 895/896: The year of the Magyars arrival in Pannonia. This year is widely accepted as the beginning of the Hungarian "Landtaking". 899: King Alfred the Great of Wessex, First King of The English, dies. 900: The oldest text discovered in the Philippines—an acquittance document in Old Javanese—is inscribed on a copperplate in Luzon. The acquittance took place on 21 April 900 and involved several aristocrats and high-ranking officials from kingdoms within the islands of Luzon, Mindanao, and Java. The document is currently called the Laguna copperplate inscription. Late 9th century: Bulgaria stretches from the mouth of the Danube to Epirus and Bosnia. Late 9th century: Pallava dynasty ends in Southern India. Late 9th century: Womb World mandala, To-ji, Kyoto, is made. Heian period. Unknown date Reign of Charlemagne, and concurrent (and controversially labeled) Carolingian Renaissance in Western Europe. An unknown event causes