The Prisoner appeared in the fortress, according to some historians, on July 24, 1785. In Russian history, this year is remembered for the Charters of Privileges granted to the nobility and cities. The place of detention for the prisoner was the Powder Cellar. The documents did not specify his first name, last name, or nickname, but referred to him as “The Nameless.” This was the punishment for the most serious crimes.

The Pugachev Rebellion frightened Catherine II so much that after the victory over the rebels, the arrest and execution of Pugachev, his family was imprisoned for life in the Keksgolm Fortress and spent about 50 years within its walls. The family of five was kept in the basements of the Round Tower, which came to be called the Pugachev Tower, starting from January 1775, immediately after Emelyan's execution.

Formally, he reigned during the first year of his life under the regency of first Biron, and then his own mother Anna Leopoldovna. The infant emperor was overthrown by Elizabeth Petrovna, spent almost his entire life in solitary confinement, and was killed by guards at the age of 23 during the reign of Catherine II while an attempt was made to free him.

The Shlisselburg Fortress almost immediately after being conquered by Peter I lost its military significance, and its casemates began to be used as a state prison.

In the Peter and Paul Fortress, two facilities were used as prisons. Initially, it was the Trubetskoy Bastion. In the first quarter of the 18th century, the casemates of the Trubetskoy Bastion were used as detention cells for the Secret Chancellery. In 1718, Tsarevich Alexei Petrovich, son of Peter I, who was accused of participating in a state conspiracy, was held here; he died (or was executed) on July 7, 1718. Later, the Alekseevsky Ravelin prison was used.

There are no reliable historical records about the origin of the well-known Moscow elder-nun who lived in seclusion for a quarter of a century in the Ivanovsky Monastery. There are no documents, no direct and precise testimonies; only tradition remains, though quite credible. Indirect evidence suggests her noble and very high birth, while vivid, direct, and accurate testimonies point to her life in seclusion. According to the monastery clerk and Moscow merchant Shepelev, Elder Dosifeya was of medium height, slender, but retained on her face "the features of former beauty; her manners and behavior revealed the nobility of her origin and education." The elder visited only the gate church of the Kazan Icon of the Most Holy Theotokos. The service was performed by her spiritual father along with the clerk. She "rarely went out to church, and then only accompanied by an assigned elder nun. At such times, the church doors were locked from the inside so that no one could enter... At her windows, covered with curtains, curiosity and rumor sometimes attracted people, but the regular attendant, who took the place of a guard, drove away the curious," reports Snegirev. A special sum was allocated for her maintenance from the treasury; she could always have a good table if she wished. The absence of the recluse’s name in the records of monastics of that time proves that special instructions were made regarding her upkeep.

The revolutionary Vera Figner is one of the few women imprisoned in the Shlisselburg Fortress; she spent 20 years there. For organizing an assassination attempt on Alexander II, she was sentenced to death, which was commuted to life hard labor.

Dostoevsky was delivered to the Peter and Paul Fortress on the night of April 23 to 24, 1849, from the Third Department of His Imperial Majesty’s Own Chancellery on the Fontanka Embankment (modern No. 15), accompanied by a gendarme lieutenant. In “individual” carriages under the guard of gendarme officers, with intervals of 10–15 minutes, thirteen of the “main culprits” were sent to the fortress.

Every step of the family was closely monitored. Any cry of Ivan Antonovich's baby was detailed in reports: “Playing with the dog, he hits it on the forehead, and when asked: ‘To whom, father, will you cut off the head?’ — he answers that it will be to Vasily Fedorovich Saltykov.” The guards also reported on each other.

On December 3, 1742, the Brunswick family was relocated to Dünamünde. In January 1744, an order followed to move them to Ranenburg, and they were almost taken to Orenburg because Captain-Lieutenant of the Guards Vymdonsky, who was entrusted with the transportation, mistook Ranenburg for Orenburg. When the family members were informed about the move to Ranenburg and that they would be seated separately in different carts—husband, wife, and children—they cried for a quarter of an hour but did not show any sign of anger.