Side by side with the cultural advance, a political reawakening of the Ukrainian people was taking place. It was appreciated by the Ukrainians that political liberty for their land and race was expressly conditioned upon the overthrow of the Czarist government. Accordingly they bent their efforts in that direction. Ukrainians organized and took a leading part in the Decembrist uprising of 1825. In the subsequent revolutionary movement they were again prominent, and two-thirds of the leaders were natives of Ukraine. The events of March, 1917, were largely made possible by the Ukrainian regiments stationed in Petrograd, who refused any further allegiance to the Romanovs and became supporters of the newly created authorities. Later on, the Ukrainians were the first of the subject nations of the Russian empire to organize their own government. On November 20, 1917, Ukraine was proclaimed an independent nation by the Central Rada, the provisional Ukrainian parliament. The struggle to win recognition for this independence is still in progress. The expediency of Ukraine's claim to exist as a self-governing nation does not, however, rest merely upon racial, ethnological and historical bases. There are primary economic considerations which press for its admittance to the circle of free nations. The Ukrainian people inhabit a land 330,000 square miles in extent, with a population of 45,000,000. This territory is not merely abundantly self-supporting, but is, in fact, one of the richest areas on the earth's surface. Four-fifths of the entire extent lie within a belt of deep, black earth, which produces bounteous crops of wheat, barley, rye, oats, sugar-beets, fruit, tobacco and vegetables. Under the Ukrainian ethnographic territory lie mineral riches: coal, petroleum, iron, manganese, salt, phosphate, kaolin, graphite and many other substances of commercial value. In the normal pre-war period, Ukraine used to supply about 5,000,000 tons of grain for export annually. Most of this was wheat. The last three years, particularly 1919, have seen good harvests in Ukraine. At the present moment, when western Europe is unable to feed herself, Ukraine has an excess remaining from the crops of 1917, 1918 and 1919, to an amount of not less than 10,000,000 tons of different kinds of grain. Besides this, the country can guarantee a minimum yearly export of 300,000 to 600,000 tons of sugar; 9,000 tons of tobacco; 17,000 tons of sugar-beet seeds; and 10,000 tons of flax and hemp yarn. Besides these products, Ukraine used to export annually before the war: 65,000 tons of eggs; 6,500 tons of raw hides; 12,000 tons of pork and dressed poultry; 9,000 tons of beef; 240,000 head of beef cattle; 15,000 head of horses; 130,000 hogs; and large quantities of wool, feathers and hops.