Notre Dame Cathedral is a major location in the films The Hunchback of Notre Dame and The Hunchback of Notre Dame II. It is here where Quasimodo has lived all his life. On the steps of Notre Dame, Judge Claude Frollo murdered Quasimodo's mother by kicking her down the steps. Enraged at this defilement, as it was holy ground and murder is not permitted, the cathedral intimidated Frollo into caring for the child lest he suffer eternal damnation and later helped to destroy him by animating one of its gargoyles into terrifying him enough to fall to his death into the lake of molten copper created earlier by Quasimodo who able to prevent Frollo's soldiers from breaking in. Its beloved bell, La Fidele, is later stolen by a gang of thieves but was later returned to its rightful place, much to the delight of Paris and the cathedral itself.
This building serves as a home to the main protagonist, Quasimodo. By law, it serves as a refuge for those who are persecuted; people pursued by the law may claim sanctuary within its walls. Examples of this include when Esmeralda was in trouble with the law and had to stay in the cathedral, she sings "God Help the Outcast" her song also lured Quasimodo, but before he could talk to her just after finishing singing the song, a parishioner who mistook him causing trouble shouts at him causing him to knock down a candlestaff and flees back to the belltower. Esmeralda was alerted by the Parishioner's shouts and follows Quasimodo, the parishioner also attempts to stop her and Djali from following him and is promptly scolded by the Archdeacon and when Quasimodo saved Esmeralda and called for sanctuary. Frollo and his soldiers attempted to break down the doors and lead the enraged citizens of Paris and French army to attack, leading Frollo's soldiers to their defeat at the hands of those within. In the films, Quasimodo seems to have a certain attachment to Notre Dame, despite his newly-found allowance of being able to interact with Parisian society. Quasimodo likely still views the cathedral as a home as he still rings and cares for its bells, each of which he has bestowed a name. In return, the cathedral shelters and protects him; when Frollo attempts to do the unthinkable and commit murder within the cathedral itself, Notre Dame animates the gargoyle he is clinging to into roaring at him before breaking off and plunging into the fiery pit below.
In Real Life
Notre Dame de Paris, also known as Notre Dame Cathedral, is a Gothic, Catholic cathedral on the eastern half of the Île de la Cité ("Island of the City") in the fourth arrondissement ("Administrative District") of Paris, France. It is the cathedral of the Catholic Archdiocese of Paris: that is, it is the church that contains the cathedra (official chair) of the Archbishop of Paris.
Notre Dame de Paris appears in two occasions. In its first appearance, Linguini passes by on his bike while on his way to kill Remy as per Skinner's instructions. In its second appearance, Linguini and Colette pass by the cathedral while rollerskating.
Mater, Finn McMissile and Holley Shiftwell drive by the cathedral after their arrival in Paris.
Throughout the first film, it is highly implied that Notre Dame has some form of sentience, likely to highlight how special it is to Paris. An example can be seen at the very beginning of the movie, which is the statues glaring at Frollo after he kills Quasimodo's mother. Also, the entire cathedral groans when Quasimodo tears down two columns to free himself and when Frollo delivers his last blasphemy whilst trying to murder Esmeralda ("And He shall smite the wicked and plunge them into the fiery pit!"), the gargoyle he is standing on immediately breaks off and plummets into the flames below after roaring at him: this highly implies that Notre Dame heard Frollo and obliged.