 Egypt and Syria played a central transit role in international trade in the Middle Ages.Early into their rule, the Mamluks sought to expand their role in foreign trade, and to this end Baybars signed a commercial treaty with Genoa, while Qalawun signed a similar agreement with Ceylon.By the 15th century, internal upheaval as a result of Mamluk power struggles, diminishing "iqtaʿ" revenues as a result of plagues, and the encroachment of abandoned farmlands by Bedouin tribes led to a financial crisis in the sultanate.