During the 19th century, farmers started to grow new crops that had greater profits. Farmers started to grow "Nicotiana tabacum" (tobacco), and farming became more common. At the middle of the 19th century, about a third of the population of Iranian Kurdistan were nomadic people. Many of the crops from Iranian Kurdistan (grains, fruits, and nuts) went out of the Qajar Empire as exports along the trade route between Tabriz and the Black Sea at Trabzon. Carriage of the exports from Kurdistan to the sea was by draught animals. The peasant farmers grew the crops, and the nomads of the tribes supplied the domestic animals for the crops' transport. (The peasant farmers also had to pay taxes and extortion to the tribes.) In 1870, 40% of Iran's international trade went through Iranian Kurdistan on the Tabriz–Trabzon trade route. However, from that time the trade route became less important. The Russian Empire completed a new railway from Baku (on the Caspian Sea) to Tbilisi and then to Poti (on the Black Sea). The British and French empires completed the Suez Canal in 1869, and because of this, many exports started to go to the Persian Gulf at Bushehr or through Baghdad at Basra. These two new trade routes meant that Kurds did not profit from the exports and the Kurdish tribes became more weak. 