The boundaries between Russia, Germany, and Austria were based upon military and strategic rather than upon racial considerations. They were the result of an attempt to strike a balance which would give some advantage to each of those powers in the event of war and place them all in a certain degree of peril. Russian Poland was thrust in between Prussia proper and the Austrian province of Galicia. It might menace the approaches to Berlin but was itself threatened in turn on either flank. Before the Russians could use Warsaw as the base of an attack upon Berlin, they must first clear East Prussia and Galicia. Nor could the Austrians attack from Galicia without exposing Cracow, the key to Vienna, itself easily assailed by the Russians. On the other hand, the Germans could advance on Warsaw direct, only at the imminent risk of being caught between the Russian armies maneuvering in Poland. Attacks upon Warsaw from both flanks by the Austrians and the Germans would have to be made in great force because the Russian position in Poland was very strong.

These conditions explain the character and nature of the first campaigns. We find Warsaw the German objective and Berlin the objective of the Russians. But we find them both campaigning in Galicia and in East Prussia. In Galicia, too, there were great wells of oil, exceedingly useful to the Germans and Austrians, and no less useful to the Russians. These eastern campaigns threatened as well the great German industrial district of Silesia. At the same time the prime object of the first Russian campaign was not strategic at all. It was to compel the Germans to transfer both men and munitions to the eastern front and hence to relieve the pressure on the French until the British could arrive.

The Russians therefore advanced early in August, 1914, along both flanks into eastern Prussia and into Galicia in considerable force and with great rapidity, despite their very inefficient equipment. Both provinces were rapidly overrun. In East Prussia toward the end of August and the beginning of September Hindenburg, as already related, defeated the Russian armies in the battles of Tannenberg and of the Masurian Lakes. To the south, in Galicia, however, the Russian advance went on unchecked, meeting apparently no real resistance. Lemberg was captured; Cracow even was threatened, and many of the passes of the Carpathians fell into Russian hands, so that by January the greater part of Galicia had been overrun, and there seemed to be some possibility that the Russians might be able to capture Przemysl and even invade Hungary.

Long before this juncture, Hindenburg attempted a direct assault upon Warsaw. Having gotten possession of East Prussia and having thus made safe his flank and rear, he did not at this time propose to pay any attention to the Russians in Galicia, knowing full well that if Warsaw should fall Galicia would be a death trap for the Russian army. From October 20 to October 27 he delivered a tremendous series of direct assaults upon the Russian lines before Warsaw and was everywhere defeated by the Grand Duke Nicholas, whose masterly retreats and sudden counter-assaults checked and slowed down the German advance and often imperiled the whole German position. With inadequate artillery and a very small supply of ammunition, he fought a masterly series of actions, which did gain the time then so essential for the French, and which did prevent the defeat of his own armies by the much larger forces of his very much better equipped foes.

General Mackensen then undertook a new assault upon Warsaw from the northwest, advancing on a broad front between the rivers Warta and Vistula. The Russian armies were of course using the Vistula as a defensive barrier but its passage did not seem difficult to the Germans. From November to February the pressure went on but without real success. The loss of men was heavy and the fact was only too conclusively established that the Vistula's heavy floods were too great a defensive barrier, when utilized by a general like the Grand Duke Nicholas, to be overcome by any direct frontal attack.

Hindenburg therefore gave up the attempt and took time to prepare a tremendous series of movements, which should sweep all before them and crush the Russian army for good. He became convinced that he had been operating on too small a scale with too few men. The full strength of the German army must be thrown upon the Russians in a series of all but simultaneous assaults. He must smite them hip and thigh. He must also campaign behind the Vistula and therefore must assail Warsaw from both flanks. He could easily cross the Vistula in East Prussia, and by advancing through Galicia in the south he could march round the great river.

The Russians had meantime made good use of their opportunity in Galicia. Przemysl had fallen on March 17. The Russian armies could now safely cross the Carpathians and assail the defenses of Cracow itself. Already in London and Paris they had begun to hope that the invasion of Hungary and an assault upon Vienna might be the next news.

Hindenburg, however, proposed to take full advantage of the large number of men the Germans could concentrate at a particular spot and especially of the greater efficiency of the German artillery. He had plenty of munitions and he knew the Russians had not. The new campaign was to be an artillery battle. He would overwhelm them by mere weight of metal thrown. He would concentrate so tremendous a fire on them that their defenses would be wiped out, and he well knew that they had not a sufficient supply of ammunition to crush his forces in the same manner when his infantry should advance. It was a mathematical calculation—so many Russians, so many guns, so much ammunition; then the infantry could stride forward over the corpses so many miles. The process could then be repeated. They could advance as fast as the German artillery could be moved forward.

By these tactics he would cut through the Russian right flank in Galicia, separate it from the Russian armies in Poland, and thus outflank the rest of the Russians in Poland and compel them to retreat on Warsaw to save themselves. The same movement would outflank the Russian center and left in Galicia and the Carpathians, which had been foolishly thinking of a descent upon Hungary. They would be compelled to retreat on Lemberg and would thus surrender without a blow the whole of Galicia and southwest Poland.

The movement was a complete success; it proceeded on schedule time, so many miles a day. Przemysl fell June 3; Lemberg was evacuated June 22; the whole of Galicia. had been cleared by June 30. Cracow, Vienna., Berlin were safe; Warsaw itself had been flanked and was in real danger.

Now, therefore, came a change in tactics. The time had arrived to begin to draw the strings of the net together. Hindenburg hoped to entice the Grand Duke Nicholas into Warsaw by not attacking in the center and by remaining up to this period quiet in East Prussia. His troops in East Prussia were already far east of Warsaw; Mackensen beyond Lemberg was also east of Warsaw. If only the Grand Duke would stay in Warsaw, the German armies could advance, the one south and the other north, and they would infallibly cut him off and destroy or capture his whole army. Thus told, the operations Hindenburg had in mind were simple in the extreme. But when such a movement had to be executed by more than a million men in a series of battles which must necessarily consume some weeks, it involved the most extraordinary foresight in planning and the greatest precision in execution. It also assumed a certain element of surprise. He had been quietly collecting enormous forces in East Prussia while Mackensen was pushing through Galicia. He had also collected a very large army in extreme East Prussia, which should be ready to assail the Russian railroads leading to Petrograd and Moscow as soon as Warsaw should fall.

On July 1, therefore, Mackensen turned north and began to press on, so many miles a day, schedule time, towards Warsaw. On July 14, the Germans moved from East Prussia south on Warsaw, being now well behind the Vistula. Thus they were approaching Warsaw in overwhelming force and with great rapidity on both flanks. The Grand Duke instantly began the evacuation of the great city and of all the Russian lines. On July 29, Mackensen reached the Lubin-Cholm Railroad on the south. Hindenburg crossed the Narew River north of Warsaw, and another huge German army was thrown across the Vistula south of Warsaw at Ivangorod. The Germans entered Warsaw in triumph on August 4, the Kaiser himself appearing for the function. The Russians evacuated of necessity nearly the whole of Poland. Hindenburg now struck southeast at Kovno, attempted to put an army in the rear of the retreating Russians. Starting August 17, the Germans pressed on toward Riga on the north and toward Vilna on the east.

For the remainder of the war some half-hearted attempts were made to push the lines somewhat further, and eventually Riga did fall into German hands. The fleet sailed up and captured some of the islands along the coast, and an attack upon Petrograd by sea was even considered. But by September, 1915, the German line reached in Poland practically the maximum of its extent until the Russian revolution in March, 1917, brought the real war in the east to an end. There was indeed little purpose in attempting to carry the war into Russia. The real foe was the Russian army, not the country itself, and the Germans believed that the army was broken and disorganized in 1915 to as great an extent as was useful to them. It was no longer dangerous, they thought, and could be further destroyed whenever they pleased. To pursue it into the marshes beyond the existing lines, to assail Petrograd or Moscow by invasion, would have been to commit the fateful error of Napoleon; to place their army at the mercy of Generals Winter and Hunger without accomplishing anything of military importance.