Sāmarrā is a town in Iraq. It stands on the east bank of the Tigris in the Salah ad Din Governorate, 125 kilometers (78 mi) north of Baghdad


History of samarra
Ancient Samarra
Though the present archaeological site covered by mudbrick ruins is vast, the site of Samarra was only lightly occupied in ancient times, apart from the Chalcolithic Samarran Culture (ca 5500–4800 BC) identified at the rich site of Tell Sawwan, where evidence of irrigation—including flax— establishes the presence of a prosperous settled culture with a highly organized social structure.

Abbasid capital In 836 the Abbasid caliphate's Turkic and Armenian slave soldiers -known as Mamluk- agitated the citizens of Baghdad, provoking riots. The capital of the Caliphate was moved from Baghdad to the new city of Samarra later that year by Caliph Al-Mu'tasim.
During this time the original pre-Islamic settlement was replaced with a new city established in 833. Samara would remain the capital of the Muslim world until 892 when it was returned to Baghdad by al-Mu'tamid. Al-Mu'tasim's successor, al-Wathiq, developed Samara into a commercial city, and it was further developed under Caliph Al-Mutawakkil.

Modern era
During the 20th century, Samarra gained new importance when a permanent lake (Lake Tharthar) was created near the town by damming the river in order to end the frequent flooding of Baghdad downstream. Many local people were displaced by the dam, resulting in a big increase in Samarra's population.
Samarra is a key city in Salahuddin province, a major part of the so-called Sunni Triangle where insurgents have been active since shortly after 2003 invasion by the United States of America. On February 22, 2006, the golden dome of the Al Askari Mosque was destroyed by bombs, setting off a period of rioting and reprisal attacks across the country which claimed hundreds of lives. On June 13, 2007, suspected al-Qaeda insurgents attacked the mosque again and destroyed the two minarets that flanked the dome's ruins. No fatalities were reported.

https://islamstory.com/en/artical/31911