Though the ink has faded and the paper is creased and yellowing at the edges, the longing in a letter penned by a United States pilot stationed in China during World War II remains evident. "Darling, it is understood that no place could really be home without you..." Major D. J. Campbell wrote to his wife in Cincinnati.

Dated 1945, the letter was never meant for the public eye. Today, it rests at Renmin University of China's museum of family letters, tucked away in the heart of Beijing.

Campbell was a member of the Flying Tigers — officially known as the American Volunteer Group of the Chinese Air Force — which was formed in 1941 by US General Claire Lee Chennault to help China in its fight against invading Japanese forces.

His letter is just one among more than 80,000 preserved in the museum's growing archive of handwritten messages between husbands and wives, parents and children, as well as soldiers and their loved ones. Many were written during the Chinese People's War of Resistance Against Japanese Aggression (1931-45), revealing stories of separation, sacrifice and the endurance of love amid one of history's darkest chapters.

One letter was from Zhao Yiman, a revered figure in the resistance movement in Northeast China. Captured in 1935 and executed the following year at just 31, she withstood brutal torture without betraying her comrades.

In her final words to her young son, she wrote: "It's my regret that I haven't fulfilled a mother's duty to raise and guide you. There will be no chance for us to meet again in this life. My most beloved child, I have no need for a thousand words to teach you. I teach you by how I have lived. When you are grown, I hope you will never forget that your mother gave her life for the country."

Another letter bears the heartbreak of Zuo Quan, a general of the army led by the Communist Party of China, who was killed in a battle in 1942. In it, he poured out his longing for his wife and daughter, torn from him by the war. "What a pity that the three of us are scattered in different places. If only we were together, how joyful that would be!" he wrote. "Zhilan! My dear, parting is easy; meeting again is so hard. It's been 21 months since we separated. When will we reunite? I miss you, I miss you!"

The war against Japanese aggression was the first major conflict and the longest-running campaign during the World Anti-Fascist War. It resulted in over 35 million Chinese military and civilian casualties.

"Amid the torrent of the war, the fierce battles on the front lines and the daily struggles of life are faithfully recorded in family letters," said Zhang Ding, the museum's deputy director. "Each wartime letter represents an individual's memory. Together, they form the collective memory of that era."

Zhang's view is echoed by Tian Yanfei, a lecturer at the Hunan Academy of Governance of the university. "China made tremendous sacrifices and contributions to the victory in the World Anti-Fascist War," Tian said. "The sorrow and sincerity captured in these letters come together to form an epic chronicle of the Chinese people's 14 years of courageous resistance."

Tian noted that wartime letters between family members serve as constant reminders that the wounds of war must not be forgotten, and that the fruits of peace must be safeguarded by all. Renmin University of China began collecting private wartime letters in 2005, and its museum of family letters continues to expand its archive.

Xinhua