Ruan and Pipa
A small pipa was found in murals of tombs in Liaoning (遼寧) province in northeastern China. The date of these tombs is about late Eastern Han (東漢) or Wei (魏) period (220-265 AD). However, the pear-shaped pipa was not brought to China from Dunhuang (敦煌, now in northwestern China) until the Northern Wei period (386-524 AD) when ancient China traded with the western countries through the Silk Road (絲綢之路). Evidence was shown on the Dunhuang Caves frescoes that the frescoes contain a large number of pipa, and they date to 4th to 5th century.
During the Han period (206 BC-220 AD), Lady Wang Zhaojun (王昭君, known as one of the Four Beauties in ancient China) departed mainland to the west and married the Grand Khan of the Huns. The marriage was meant to maintain peace between the two ancient countries. On her way to the west, she carried a pipa on the horse. Looking back today, her pipa must have been a ruan-type instrument with a round sound box, since the pear-shaped pipa was not brought to China until the Northern Wei Dynasty after the Han Dynasty. However, in almost all the portraits and dramas, Lady Zhaojun's pipa is displayed inaccurately. The pipa is usually shown with a pear-shaped sound box (as in today's pipa), rather than a round sound box.
Note that the frets on all Chinese lutes are high so that the fingers never touch the actual body—distinctively different from western fretted instruments. This allows for a greater control over timbre and intonation than their western counterparts, but makes chordal playing more difficult.
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