By withholding the tribute which Irene had agreed to pay to the caliph Hārūn al-Rashīd, Nikephoros committed himself to a war against the Arabs.

With a succession struggle enveloping the caliphate on the death of Hārūn al-Rashīd in 809, Nikephoros was free to deal with Krum, Khan of Bulgaria, who was harassing his northern frontiers and had just conquered Serdica ( Sofia ).

it: Hārūn al-Rashīd

In the year 599 AH during circumambulating the Kaaba, he encountered the son of Caliph Hārūn al-Rashīd, who had been dead for four centuries and was famous for choosing Saturday for work to gather food for rest of the week.

Ibn ‘ Arabī asked him: “ Who are you ?” He replied: “ I am al-Sabtī ibn Hārūn al-Rashīd .” Later Ibn ‘ Arabī asked him: “ What was the reason of choosing Saturday for work ?” He replied: “ As God has made this universe in six days from Sunday to Friday, and he rested on Saturday, so I, as His servant worked on Saturday and devoted myself to worshipping Lord for the rest of the week .” In another glorious vision at Kaaba Ibn ‘ Arabī saw his forefathers and asked one of them his time, he replied he had been dead around forty thousand years ago.

* Ulrich Alertz, The Horologium of Hārūn al-Rashīd Presented to Charlemagne – An Attempt to Identify and Reconstruct the Clock Using the Instructions Given by al-Jazarī, in: Variantology 4.

Historical reports attest that another ‘ Abbāsī caliph Hārūn al-Rashīd too expressed similar wishes before Imām Mālik who remained unmoved.

It was under Hārūn ar-Rashīd that Baghdad flourished into the most splendid city of its period.

et: Hārūn ar-Rashīd

In the Hebrew Bible and the Qur ' an, Aaron ( or ; Ahărōn, Hārūn, Greek ( Septuagint ): Ααρών ), who is often called "' Aaron the Priest "' () and once Aaron the Levite () ( Exodus 4: 14 ), was the older brother of Moses, ( Exodus 6: 16-20, 7: 7 ; Qur ' an 28: 34 ) and a prophet of God.

The latter allegation is specified in the following tale ; Hārūn loved to have his own sister Abbasa and Ja ' far with him at times of recreation.

This gave Khalid bin Barmak considerable influence, and his son Yaḥyá ibn Khālid ( d. 806 ) was the vizier of the caliph al-Mahdi ( ruled 775 – 785 ) and tutor of Hārūn al-Rashid ( ruled 786 – 809 ).

Hārūn was born in Rey.

Hārūn was strongly influenced by the will of his mother in the governance of the empire until her death in 789.

Since Muslim etiquette forbade their common presence, Hārūn had Ja ' far marry Abbassa on the understanding that the marriage was purely nominal.

Hārūn, while on a pilgrimage in Mecca, heard the story and ascertained that the tale was probably true.

Hārūn became caliph when he was in his early twenties.

Imam Reza was buried beside Al-Ma ' mun's father Hārūn al-Rashid.

Ali al-Ridha was not looked upon favorably by Hārūn Rashīd, and the people of Medina were disallowed from visiting Ali al-Ridha and learning from him.

* al-Fadl ibn al-Rabi, an Abbasid loyal civil servant very close to Hārun and a rival of the Barmakids, convinced Hārūn to assign spies to watch them, and that is how he found out about Yahya Ibn Abdullah al-Talibi's incident.

Yahya had aided Hārūn in obtaining the caliphate, and he and his sons were in high favor until 798, when the caliph threw them in prison and confiscated their land.

In 796, Hārūn decided to move his court and the government to Ar Raqqah at the middle Euphrates.

* The Yahya ibn Abdullah al-Talibi incident: In AH 176, Yahya ibn Abdullah went to Daylam in Persia and called for rule by himself in place of Hārūn.

Hārūn managed to capture him and ordered that he be confined to house arrest at al-Fadl's house in Baghdad.

In 803, the family lost favor in the eyes of Harun al-Rashīd, and many of its members were imprisoned.

According to Rit Nosotro, Harun al-Rashīd found his chief pleasure in the society of his sister Abbasa and Jafar bin Yahya, and, in order that these two might be with him continuously without breach of the restrictions on women, he persuaded them to contract a purely formal marriage.

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Athens (;, Athína ; ; Katharevousa: Ἀθῆναι, Athinai ; Ancient Greek: Ἀθῆναι, Athēnai ) is the capital and largest city of Greece.

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Çatalhöyük (; also Çatal Höyük and Çatal Hüyük, or any of the three without diacritics ; çatal is Turkish for " fork ", höyük for " mound ") was a very large Neolithic and Chalcolithic settlement in southern Anatolia, which existed from approximately 7500 BC to 5700 BC.

The Chechen Republic (;, Chechenskaya Respublika ;, Noxc ̈ iyn Respublika ), commonly referred to as Chechnya (;, Chechnya ;, Noxc ̈ iyc ̈ ó ), also spelled Chechnia or Chechenia, sometimes referred to as Ichkeria (), is a federal subject ( a republic ) of Russia.