“Not in contemplative peace and snug homeliness, as is appropriate to the birthday of a general, of his own early morning coffee, but outside in the iron field of the new battles, which thunder and lightning between the Vistula and the Dniester will Hindenburg, Germany’s brilliant champion, celebrate his sixty-seventh birthday. And from Königsberg to Strassburg, from Cologne and Aix to Breslau and Przemysl, from the North Sea to the Adriatic, all Germans and all dwellers in the Habsburg lands whom Hindenburg now approaches in the guise of a helper will greet the day with a heartfelt joy.” In following the record of the operations it must be borne in mind that the huge Russian land-frontier of some fifteen hundred miles towards Austria and Germany is for the most part the frontier of Russian Poland. This province, in its relation to the bulk of the Russian territory, has been picturesquely likened to “a huge bastion” wedged between German territory to north and west and Austrian territory to the south. But it is a political rather than a natural frontier, “marked out in somewhat arbitrary fashion when, after the turmoil of the Napoleonic wars, the map of Europe was being resettled at the Congress of Vienna.” One may say roughly that this mass of Russian Poland projects between German and Austrian territories for about two hundred miles from north to south and two hundred and fifty miles from east to west. Russia has a group of fortresses in the plain of Poland, three of which are sometimes known as “the Polish Triangle,” with a fourth fortress acting as a sort of outpost or “triangle” looking towards the German frontier. Warsaw (one of the world’s greatest fortresses), Ivangorod, and Brest-Litovski are these three places of strength constituting a “triangle,” the outpost fortress being Novo Georgievsk, at the confluence of the Vistula and Narev rivers. Then, along the latter river and the Niemen runs a chain of fortified river-crossings, supplying “a defence line for the region north of the Pripet marshes, and a well-protected concentration line for armies destined to operate against East Prussia.” Finally, this well-planned fortress system is completed by a group of fortified towns between the marsh country and Galicia. It was the effective “screen” of this system of strong places that enabled the mobilisation of the Tsar’s vast armies to be carried out so successfully.