A Columbia University fraternity brother is suing over his expulsion from the Ivy League school amid accusations he raped a female student — claiming he shouldn’t be held accountable because he was too drunk.

The former student — identified as “John Doe” in his Manhattan Supreme Court lawsuit — says he only has “flashes” of a sexual encounter with a coed in her dorm room on Dec. 13, 2017.

He says he blacked out to the point of talking with a German accent and claiming blood ties to Nazis.

The fraternity brother, who hails from Oklahoma, admits to downing seven drinks in 45 minutes at a fraternity formal around midnight on Dec. 13.

“The alcohol beverages greatly affected [him] because he did not eat much dinner and had not been consuming alcohol during the fall 2017 semester,” he says in court papers.

He remembers getting into an Uber shortly after 1 a.m. His next memory “was waking up partially clothed in an unfamiliar room in a stranger’s bed on the morning of Dec. 13, 2017,” his suit says.

“He did not know where he was, how he arrived there, whose bed he was in, or who was in the bed with him,” he says.

The next day, when another Columbia student reached out to discuss the frat formal, he “began having flashes of memory regarding the gap in time on Dec. 13, 2017,” the suit says.

This is what he says he remembers:

He was cradling a drink in the woman’s dorm room and having difficulty walking to the bathroom because he was so wasted. He “believes” the woman then kissed him, helped him undress, and “opened her legs and scooted back to indicate that she wanted oral sex.”

He also thinks she got a condom and then climbed on top of him for sex. She kicked him out the next morning at 6 a.m. because she had to be at work in two hours, he says.

After he slept off his hangover he called his dad for advice claiming he “felt taken advantage of in his intoxicated state,” but his “father discouraged” him from reporting the encounter to Columbia officials, the suit says.

By Dec. 20, 2017 the woman had told school administrators he had attacked her. He turned around a month later and said the coed was the one who sexually assaulted him “due to his incapacitation resulting form his intoxicated state.”

The university launched a probe into the competing claims.

“During the investigation, [he] was made aware that complainant observed [him] speak in a German accent, falsely assert that his ancestors were Nazis, and request the use of her shower — clear indications that he was intoxicated to the point of incapacitation,” his suit says.

In June a panel determined he’d committed the assault, finding that he wasn’t actually blacked out and ignored the woman’s pleas for him to “stop.”

The hearing panel dismissed his claims against the woman.

He insists the determination was unfair because the panel ignored favorable evidence and treated him differently than another female victim who’d also blacked out.

“Instead of following their usual procedure of carefully considering any facts that an alleged victim of sexual assault could glean from a blackout, [CU] peremptorily rejected [John Doe’s] recounting of the night in question, presumably because he is male,” he says in the gender bias suit.

He was expelled in July and was not allowed to graduate.

He’s suing for his diploma and other damages. His lawyer did not return calls for comment.

Reps for Columbia also did not immediately return messages seeking comment.