Adopted from the book : "Fadak in History" by : "Shahid Muhammad Baqir as-Sadr"
Abul Abbas as-Saffah,the first Abbasid caliph,gave Fadak back to Abdullh bin al-Hassan bin al-Hussayn bin Ali bin Abu Talib.Then Abu Ja'far al-Mansour seized it during his reign from al-Hassan's family.Al-Mahd bin al-Mansour gave it back again to the Fatimites, whereas Musa bin al-Mahdi seized it again from them.1
It remained in the Abbasid 'hands until al-Ma'moon came to the caliphate in 210 AH and gave it back to the Fatimites.He wrote tohis wali of Medina Qathm bin Ja'far; "Amirul mu'mineen (al-Ma'moon) in his position to thereligion of Allah and the caliphate of the prophet and his kindship with him worthier to obey the prophet's Sunna and to carry out his orders.He has to SUPmit to those,whom the prophet had donated or gifted with gifts or charities. Amirul mu'mineen looks forword to the blessings of Allah and His safeguard and to be able to do what may bring him closer to Allah.The prophet had given Fadak to Fatima and that was a very will-known matter without any doubt about it among the prophet's family. She kept on claiming that Fadak was hers and she was the worthiest to be believed.Amirul mu'mineen thinks that he has to give it back to Fatima;s heirs approaching to Allah by achieving His justice and to be fixed in his books and to be sent in letters to his walis. It it was announced in every season (of hajj) after the death of the prophet (s) that whoever had a charity, a gift or he was promised of that, he was to mention that and to be granted what he was promised of, so Fatima was worthier to be believed in her claim about what the prophet had granted her.Hence amirul mu'mineen writes to al-Mubarak at-Tabari ordering him to give Fadak back to the heirs of Fatima,the daughter of prophet, with all of its limits, rights, slaves, yields and others relating to it.It is to be given to Muhammad bin Yahya bin al-Hussayn bin Zeid bin Ali bin al-Hussayn bin Ali bin Abu Talib and Muhammad bin Abdullah bin al-Hassan bin Ali bin al-Hussayn bin Ali bin Abu Talib,whom amirul mu'mineen entrusts with to be responsible of it to and to hand it over to its possessors.know well that this is the opinion of amirul mumineen and this what Allah has inspired to him with obeying him and to be closer to him and his messsenger (s). Try to inform of it and treat Mohammad bin yahaya and mohammad bin Abdullah as you treated al-mubarak at-tabari before.Help them to repair it and improve its yields insha Allah. With my salaam."2
When al-Mutawakkil became the caliphate ,he seized the Fadak from Fatimites and gave it to Abdullahi bin Omar al-Baziyar.It had eleven date palms planted by the holy hands of the prophet himself.Abdullah bin Omar al-Baziyar sent a man called Bishran bin Abu Umayya ath-Thaqafi to Medina.He cut off those date-palms when he came back to Basra. He was affilicted with hemiplegia.3
The reletion between the Fatimites and Fadak ended in the days of Mutawakkil when he donated it to Abdullahi bin Omar al-Baziyar.4
This was a summary account about the confused history of Fadak which was woven by the inclination and formed by the fancias according to what was required by the covetousnes and the temporary policies. In spite of that,history did not miss moderation and fairness in some different times and circumstances where Fadak was given back to its real possessors.It was noticeable that problem of fadak took a great importance in the Islamic soceity and the rulers' attention.
Hence you see that its solution differed according to the different policy of the state and SUPmitted to the mainstream of the caliph towards the prophet's family directly. If the caliph had a fair look and moderate thought,he would give Fadak back to the Fatimites but if he was not so, seizing Fadak was on the top of the caliph's list of the priorities.
1- Sharh Nahjul Balagha, vol.16 p. 216-217
2- Futoohul Buldan p.46-217
3- Sharh Nahjul Balagha vol.16, p.217