The People’s Republic of China basked in its 60th anniversary on Thursday with jaw-dropping pageantry, but there were no solemn pauses for the lives lost during the Communist Party’s rise to power  not for the estimated tens of millions who died during the civil war, nor the millions of landlords, Nationalist sympathizers and other perceived enemies who were eradicated during Mao’s drive to consolidate power.

Image Meng Qinghua said he ate corncobs and bark to survive the famine. Credit... Shiho Fukada for The New York Times

“Changchun was like Hiroshima,” wrote Zhang Zhenglu, a lieutenant colonel in the People’s Liberation Army who documented the siege in “White Snow, Red Blood,” a book that was immediately banned after publication in 1989. “The casualties were about the same. Hiroshima took nine seconds; Changchun took five months.”

The 40,000 who survived did so by eating insects, leather belts and, in some cases, the bodies that littered the streets. By the time Communist troops took over the city, every leaf and blade of grass had been consumed during the final desperate months.

There are no monuments or markers recalling the events that decimated Changchun’s populace. Most young people have no knowledge of the darker aspects of the siege, and the survivors, now in their 70s and 80s, are reluctant to give voice to long-buried trauma. “I’ve always heard that Changchun was captured without bloodshed,” Li Jiaqi, a 17-year-old high school student, said as she sat on the steps in front of the city’s Liberation Memorial.

Chinese scholars have largely steered clear of the subject. Several historians, when asked about the episode, declined to be interviewed. Zhou Jiewen, a retired nuclear physicist in Changchun who has become a self-taught expert on the siege, explained that many key details, if widely disseminated, would tarnish the army’s reputation as defenders of the common man. Those include shooting civilians who tried to escape the city and ignoring the pleas of mothers holding aloft starving children on the other side of the barbed-wire barricades. “To cause so many civilians to die was a great blunder by the P.L.A. and tragedy unparalleled in the civil war,” Mr. Zhou said.