Jonathan Majors, a rising movie star who was found guilty last year of assaulting and harassing his then-girlfriend, Grace Jabbari, was sentenced to 52 weeks of domestic violence programming on Monday in Criminal Court in Manhattan.

Mr. Majors, in a dark turtleneck, had no immediate reaction as the sentence was announced. He could have faced up to a year in jail.

Mr. Majors’s conviction in December on assault and harassment charges — one misdemeanor and one violation — left his career in tatters. Marvel Studios dissolved its relationship with him. Searchlight Pictures said that it would not release “Magazine Dreams,” in which Mr. Majors played a fury-filled steroid-taking bodybuilder.

And after the verdict, two women who had dated Mr. Majors between 2013 and 2019 described him to The New York Times as a controlling, threatening figure who had abused them and isolated them from friends and career pursuits. Mr. Majors denied the allegations.

Ms. Jabbari met Mr. Majors in 2021 on the set of the Marvel movie “Ant-Man and the Wasp: Quantumania,” where she was working as a movement coach and he was playing a time-traveling supervillain named Kang the Conqueror.

The two lived together in London and New York, but their relationship splintered early one morning last March. Mr. Majors and Ms. Jabbari were inside a hired S.U.V. in Lower Manhattan when she said she saw a text message on his phone from another woman. Ms. Jabbari has said that she grabbed the phone and that Mr. Majors tried to pry it from her hand, breaking one of her fingers. He was arrested later that day.

Most people facing misdemeanor charges look for a way to resolve them with a plea agreement. But Mr. Majors went to trial late last year, apparently hoping for an acquittal that could revive his career. His lawyer, Priya Chaudhry, called Ms. Jabbari’s account of what took place inside the S.U.V. a “complete lie” and contended that Mr. Majors had been the victim.

Ms. Jabbari was arrested in October on a countercomplaint by Mr. Majors and charged with misdemeanor counts of assault and criminal mischief. The Manhattan district attorney’s office declined to proceed with that case, saying at the time that it lacked “prosecutorial merit.”

During his trial in December, Mr. Majors walked through courtroom hallways wearing sunglasses, sat at the defense table in the well of the courtroom with a gilded Bible and greeted supporters with kisses.

Ms. Jabbari took the stand, crying at times as she described a turbulent relationship in which Mr. Majors yelled at and berated her and once hurled a candle at her. After she grabbed his phone in the S.U.V., Ms. Jabbari testified, Mr. Majors twisted her hands and right arm and struck her in the head.

Ms. Chaudhry said Ms. Jabbari had falsely accused Mr. Majors as revenge because he had ended their relationship. After the S.U.V. ride, Ms. Chaudhry added, Ms. Jabbari went dancing with people she had met that night, letting some of them “twirl her ballroom style, while she spins on the very finger she now claims was freshly broken.”

While testifying, Ms. Jabbari said that she went dancing because she didn’t “want to be alone at that point.”

In her summation, Ms. Chaudhry depicted Ms. Jabbari as having given inconsistent testimony filled with contradictions and urged jurors to reject her “pretty little lies.” A prosecutor, Kelli Galaway, told jurors that the case was about “control, domination, manipulation and abuse,” saying that Mr. Majors had harassed and assaulted Ms. Jabbari and cut her off from friends and family.

An audio recording from 2022 played at one point during the trial offered some insight into how Mr. Majors may have viewed himself and his relationship with Ms. Jabbari. He told her she should care for him as Coretta Scott King had cared for the Rev. Dr. Martin Luther King Jr. and as Michelle Obama cared for former President Barack Obama.

“I’m a great man. A great man. I am doing great things,” Mr. Majors said, adding: “The woman that supports me, the one I support, needs to be a great woman and make sacrifices.”

Few actors have fallen as quickly and dramatically as Mr. Majors. And few actors had seemed as ready-made for stardom.

Soon after graduating from the Yale school of drama, Mr. Majors was cast in “The Last Black Man in San Francisco,” a 2019 film about life in an increasingly gentrified city. Other roles followed. In 2020 he was given the part of Kang, a character who was to appear in several Marvel films, including “Avengers: The Kang Dynasty,” set for 2026, and “Avengers: Secret Wars,” planned for 2027.

With a seemingly secure future as an anchor actor in what were seen as likely blockbusters, Mr. Majors also explored more complex roles. Critics praised his nuanced portrayal in “Magazine Dreams” of an awkward character who is driven by a thirst for fame and plagued by self-doubt and rage.

There was also a volatile side to Mr. Majors himself, according to some people who knew him before he joined the Marvel universe. On the set of the HBO series “Lovecraft Country,” he was said to have had confrontations with female co-workers that led them to complain to the network, The Times found in interviews with his former colleagues.

A few weeks after the verdict in the assault trial, Mr. Majors appeared on ABC’s “Good Morning America,” where he said he had been “absolutely shocked” by the jury’s decision and continued to dispute Ms. Jabbari’s account.

Last month, Ms. Jabbari sued Mr. Majors in Federal District Court in Manhattan, accusing him of battery, infliction of emotional distress and defamation. Her complaint said that he had engaged in “a pattern of pervasive domestic abuse” in London, New York and Los Angeles and on one occasion had banged her head against a marble floor, tried to strangle her and threatened to kill her.

Ms. Chaudhry did not respond to a request on Friday for comment on that lawsuit. Just after it was filed, she said that Mr. Majors was preparing a countersuit.