1911 Encyclopædia Britannica, Volume 6… (1911)
“ Passing over trade agreements affecting the Eastern empire, the modern commercial treaty system came into existence in the 12th century. Genoa, Pisa and Venice were then well-organized communities, and were in keen rivalry. Whenever their position in a foreign country was strong, a trading centre was established, and few or no specific engagements were made on their part. But in serious competition or difficulty another course was adopted: a formal agreement was concluded for the better security of their commerce and navigation. ”
