Halime Sultan was of Abkhazian origin. She married Mehmed at when he was still a prince and the governor of Saruhan (Manisa) Sanjak. After Sultan Murad III's death in 1595, she came to Istanbul along with Mehmed. In Istanbul, her son Mahmud was very popular with the janissaries. However, Halime was not favored by Safiye.

She send a message to a religious seer for she was superstitious to know if her son would become the next Sultan, and how much longer her husband would reign. The man answered, but the message was intercepted by Abdürrezzak Agha, the chief black enuch of the imperial harem, and who later gave it to Mehmed and Safiye, instead of her. The message said that Mehmed would die within six months without showing whether by death or deposition, and her son will become the next Sultan. Safiye incensed Mehmed, and he had Mahmud examined, who indeed knew nothing of his mother's action.

Mahmud's followers who were supposed to be involved in the matter were thrown into the sea. It was also rumored that she was also executed. However, she was send to the Eski (old) Palace located at the Beyazıt Square by the end of June. Mehmed died just six months after Mahmud's death. On Friday January 9, Safiye Sultan, along with Şehzade Mustafa were also send to the Eski Palace. Between Mehmed's death and Mustafa's enthronement her stipend consisted of 100 aspers a day.

When Mustafa ascended the throne in 1617 she became the Valide Sultan as well as a regent and wielded a great power. No one had expected that Mustafa, who suffered from severe emotional problems, would become sultan, and so she had not enjoyed a position of much status within the imperial harem. She received 3,000 aspers although her mother-in-law Safiye Sultan was still alive.

She had a potential ally in Kara Davud Pasha, but during Mustafa's first reign which lasted for only three months, she was unable to exploit her relationship by appointing Davud Pasha vizier. One of the few political alliances the valide was able to forge with her son's sword-bearer, Mustafa Agha, a high ranking inner palace officer, who was brought out of the palace and awarded the prestigious and strategically vital post of governor of Egypt on condition that he would marry the Sultan's wet nurse. Within a few moths the pasha was brought back to Istanbul as grand vizier.

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Wikipedia