China, or rather Tartary, the capital of which was Albracca, according to Orlando Furioso. It was called Khita'i by the Tartars, and China was first entered by Europeans in the Middle Ages from the side of Tartary.
“Better fifty years of Europe than a cycle of Cathay.” Tennyson: Locksley Hall.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Cathay' from Infoplease: