The Holy Roman Empire never had a single permanent/fixed capital city. Usually, the Holy Roman Emperor ruled from a place of his own choice. This was called an imperial seat. Seats of the Holy Roman Emperor included: Aachen (from 794), Palermo (1220–1254), Munich (1328–1347 and 1744–1745), Prague (1355–1437 and 1576–1611), Brussels (1516–1556), Vienna (1438–1576, 1611–1740 and 1745–1806) and Frankfurt am Main (1742–1744) among other cities.
The first libraries in Muslim lands were not necessarily for the public, but they contained much knowledge. The need for the preservation of the Quran, the Muslim holy book, and the Traditions of Muhammad, the prophet of Islam, is what led to the collection of writings in the Muslim world. Where traditions and history used to be oral, the need to preserve the words of the Quran necessitated a method of preserving the words by some means other than orally. Mosques that were the center of everything in a Muslim society's day-to-day life became also libraries that stored and preserved all knowledge, from the Quran to books on religion, philosophy and science. By the 8th century, first Iranians and then Arabs had imported the craft of papermaking from China, with a paper mill already at work in Baghdad in 794 then called Bagdatikos.