Why did mathematical books written in Chinese circulate across East Asia?

Mathematical books written in Chinese circulated across East Asia primarily because Japan, Korea, and Vietnam adopted the Chinese writing system and other cultural institutions at an early stage in their histories.1

Because this logographic system is capable of representing different spoken forms, it functioned as a common medium of communication across the region, allowing scholars who spoke mutually incomprehensible languages to read the same texts. Consequently, it is often more accurate to refer to this tradition as "mathematics in Chinese characters" rather than strictly "Chinese mathematics," as these works formed a shared scholarly foundation throughout East Asia.12

These texts, such as the Ten Classics of Mathematics and later works like the Suanfa tongzong, were imported and studied by scholars in neighboring countries to learn advanced algorithms, such as those for solving systems of linear equations or root extraction. This flow of scientific literature, which began as early as the 7th century, deeply influenced the development of mathematical traditions in countries like Japan, providing the context for their later engagement with Western mathematics.341