Her first marriage was disrupted by her half-brother Levan II Dadiani, Prince of Mingrelia, in response to Simon Gurieli's patricidal coup.

The wedding entourage was a thousands-strong army, which had to fight their way to Kartli against the forces of the principal opponent of the union, King George III of Imereti, an ally of Rostom's major foe, King Teimuraz I of Kakheti, Beyond being a factor of rapprochement between Mingrelia and Kartli, Mariam, a devout Christian, acted as a protector of Georgian Christianity in lieu of her Muslim and religiously tolerant husband and helped relax religious tension in the country.

Defeated and captured at Lanchkhuti, Simon lost his throne, sight, and family; Levan had him blinded, installed a loyal regime in Guria, and took Mariam and her son with him to Mingrelia.

Rostom, a recent widower of around 70, was a Muslim Georgian, a natural son of the late king of Kartli, David XI (Daud-Khan).

But Rostom's control otf Kartli was challenged by his deposed predecessor Teimuraz I, of the Kakhetian Bagrationi, who had spent decades fighting against the Iranian hegemony.

The union also furthered Levan II's desire to have King George III of Imereti, an in-law and ally of Rostom's arch-rival Teimuraz, in check.

Shah Safi sent wedding presents, paid Dadiani 50,000 marchil (about 1.5 tones of silver) and granted him an annual salary of 1,000 tumans (gold coins of 3 grams).

George III of Imereti blocked the border with Kartli, compelling Rostom's wedding suite to take a circuitous route via Akhaltsikhe, and intercepted Dadiani on his way to the marriage, but he was defeated and taken prisoner by Levan at the Kaka Bridge near Baghdati.

Rostom, an Iranian-raised Muslim known for his religious tolerance and determined to keep Kartli at peace and consolidate his hold of the country under the Safavid patronage, acceded to the request of his Christian bride and the ceremony was held in Christian rites, with the nominal ritual baptism of the king prior to the wedding, as reported by the Italian eyewitness, Don Pietro Avitabile.

Anxious to secure the dynastic continuity in Kartli, he first adopted Mariam's son of her first marriage to Gurieli, Prince Otia, who was married to a daughter of Zaal, Duke of Aragvi.

[16] Pursuant to the shah's order, Vakhtang, then aged 40, reluctantly divorced Princess Rodam Orbeliani, by whom he had several children, and married his adopted mother, the queen dowager Mariam.

In the subsequent years, the aging queen Mariam was less actively involved in the politics,[3] although she influenced her husband's decision to more energetically intervene in the power struggles in Mingrelia and Imereti in 1661.