This article introduces more than 200 letters discovered by the author in the Leiden University Library between Dutch sinologist Gao Luopei and Chinese scholars, qin players, calligraphers and painters, and political and business elites. These letters were mainly written between 1943 and 1948. The author believes that these letters can make up for the shortcomings of previous research. Therefore, this article divides these letters into three categories, exploring Gao Luopei's interactions with scholars of the Republic of China, demonstrating his respect and equal communication with Chinese scholars, as well as the acceptance of his achievements in Sinology by the academic community of the Republic of China.

1、 Research and discuss literary matters, exchange knowledge and skills

Dutch sinologist Gao Luopei is full of interest in traditional Chinese culture and has written several specialized books on Sinology, such as "Qin Dao", "Ji Kang and His Qin Fu", and "Collection of the Ming Dynasty Buddhist Master Donggao". He actively communicates with Chinese scholars to deepen research and improve academic level. In 1944, Gao Luopei consulted the architect Liang Sicheng on the evolution of Chinese furniture and interior decoration, and Liang Sicheng provided detailed responses and relevant literature. Gao Luopei has a deep friendship with Ma Heng, the director of the Palace Museum, and the two frequently communicate to discuss academic issues such as seal carving and Chinese characters. Gao Luopei is sensitive to the evolution of Chinese characters and adept at combining foreign religions and local customs for research. Even though he was in a foreign country, Gao Luopei consulted Chinese scholars on Sinology issues through letters. He has high praise for ancient Chinese poetry, but regrets that he cannot create poetry with beautiful imagery, so he often seeks advice from Chinese poets. The correspondence between politician Chen Lifu and Gao Luopei mainly discussed academic issues, including borrowing Xun instruments and appreciating Gao Luopei's works. Gao Luopei's research fields are extensive, including Sanskrit and Tibetan Buddhism, so scholars in related fields also seek his advice.

2、 Lecture invitation and journal manuscript invitation

Discussed the academic exchange between Dutch sinologist Gao Luopei and Republican scholars during the Anti Japanese War. Gao Luopei was invited to Fudan University to give an academic speech on the topic of "The Influence of Ming Dynasty Buddhist Master Donggao and Japanese Culture", and received positive feedback. He established close contact with Professor Fang Hao from the Department of History at Fudan University. Fang Hao once invited Gao Luopei to contribute, and his article "Preface to the Collected Works of Master Donggao" was later published in the "Truth Magazine". Gao Luopei also created a calligraphy horizontal inscription "Fudan" for Fudan University. In addition, Gao Luopei's English translations have also been published in the English journal "Tianxia".

3、 Evaluate works and recommend scholars

Before going to China, Gao Luopei had published several monographs on Sinology, but due to language and publishing location limitations, the domestic academic community knew very little about it. His collection of books on the late Ming Dynasty righteous monk Donggao Zen Master was written in Chinese and published in Chongqing, with a wide influence. Scholars of the Republic of China have given positive evaluations to this book, such as Xu Shiying and Wang Pengsheng writing prefaces, and Gu Jiegang, "Gu" and other scholars commenting on it in publications such as "Historical Journal", affirming its academic value while pointing out writing errors. Gao Luopei himself also showed a humble attitude towards scholarship. In addition, Gao Luopei had frequent correspondence with Chinese scholars, involving academic discussions, exchange of works, and introduction of scholars, demonstrating his close interaction with scholars of the Republic of China. These letters are rich in content and sincere in emotions, reflecting Gao Luopei's profound influence on academia and interpersonal relationships.