Porcelain 'monk's cap' ewer, Ming dynasty, Yongle period (1403-1424). Porcelain, Jingdezhen ware; Height: 19.40cm; Width: 19.20cm. British Museum, 1952,0512.1. Photo: © Trustees of the British Museum

Yongle (reigned 1403-24) was the third emperor of the Ming dynasty. Though his father was the first emperor, Hongwu (reigned 1368-98), Yongle usurped the throne from Hongwu's designated successor. He therefore needed to prove the legitimacy of his reign. Yongle honoured his father with elaborate Buddhist rituals and the building of a nine-storey pagoda faced with white porcelain bricks. White is the colour of mourning and filial piety in China and has strong associations with imperial ceremony.

Recent excavations at Jingdezhen (the site of the imperial kilns) clearly reveal Yongle's taste for white; 98% of the ceramics found in the stratum attributed to his reign are white porcelain. The purity of the body and glaze resulted in wares superior to any that had gone before. They are often called 'sweet white wares'.