security function as well. On Strategy, from the 6th century, offers advice about foreign embassies: "[Envoys] who are sent to us should be received honourably and generously, for everyone holds envoys in high esteem. Their attendants, however, should be kept under surveillance to keep them from obtaining any information by asking questions of our people." Medieval and early modern Europe In Europe, early modern diplomacy's origins are often traced to the states of Northern Italy in the early Renaissance, with the first embassies being established in the 13th century. Milan played a leading role, especially under Francesco Sforza who established permanent embassies to the other city states of Northern Italy. Tuscany and Venice were also flourishing centres of diplomacy from the 14th century onwards. It was in the Italian Peninsula that many of the traditions of modern diplomacy began, such as the presentation of an ambassador's credentials to the head of state. Modernity From Italy, the practice was spread across Europe. Milan was the first to send a representative to the court of France in 1455. However, Milan refused to host French representatives, fearing they would conduct espionage and intervene in its internal affairs. As foreign powers such as France and Spain became increasingly involved in Italian politics the need to accept emissaries was recognized. Soon the major European powers were exchanging representatives. Spain was the first to send a permanent representative; it appointed an ambassador to the Court of St. James's (i.e. England) in 1487. By the late 16th century, permanent missions became customary. The Holy Roman Emperor, however, did not regularly send permanent legates, as they could not represent the interests of all the German princes (who were in theory all subordinate to the Emperor, but in practice each independent). Between 1500 and 1700 rules of modern diplomacy were further developed. French replaced Latin from about 1715. The top rank of representatives was an ambassador. At that time an ambassador was a nobleman, the rank of the noble assigned varying with the prestige of the country he was delegated to. Strict standards developed for ambassadors, requiring they have large residences, host lavish parties, and play an important role in the court life of their host nation. In Rome, the most prized posting for a Catholic ambassador, the French and Spanish representatives would have a retinue of up to a hundred. Even in smaller posts, ambassadors were very expensive.