Two days after the arrival of the Turkish host the trenches were opened, the cannon placed, and the siege of Vienna began.  For more than two centuries the conquerors of Constantinople had kept their eyes fixed on this city as a glorious prize.  Now they had reached it, and the thunder of their cannon around its walls was full of threat for the West.  Vienna once theirs, it was not easy to say where their career of conquest would be stayed.

Fortunately, Count Ruediger was an able and vigilant soldier, and defended the city with a skill and obstinacy that baffled every effort of his foes.  The Turks, determined on victory, thundered upon the walls till they were in many parts reduced to heaps of ruins.  With incessant labor they undermined them, blew up the strongest bastions, and laid their plans to rush into the devoted city, from which they hoped to gain a glorious booty.  But active as they were the besieged were no less so.  The damage done by day was repaired by night, and still Vienna turned a heroic face to its thronging enemies.

Furious assaults were made, multitudes of the Turks rushing with savage cries to the breaches, only to be hurled back by the obstinate valor of the besieged.  Every foot of ground was fiercely contested, the struggle at each point being desperate and determined.  It was particularly so around the Loebel bastion, where scarcely an inch of ground was left unstained by the blood of the struggling foes.

Count Ruediger, although severely wounded, did not let his hurt reduce his vigilance.  Daily he had himself carried round the circle of the works, directing and cheering his men.  Bishop Kolonitsch attended the wounded, and with such active and useful zeal that the grand vizier sent him a threat that he would have his head for his meddling.  Despite this fulmination of fury, the worthy bishop continued to use his threatened head in the service of mercy and sympathy.

But the numbers of the garrison grew rapidly less, and their incessant duty wore them out with fatigue.  The commandant was forced to threaten death to any sentinel found asleep upon his post.  A fire broke out which was only suppressed with the greatest exertion.  Famine also began to invade the city, and the condition of the besieged grew daily more desperate.  Their only hope lay in relief from without, and this did not come.

Two months passed slowly by.  The Turks had made a desert of the surrounding country, and held many thousands of its inhabitants as prisoners in their camp.  Step by step they gained upon the defenders.  By the end of August they possessed the moat around the city walls.  On the 4th of September a mine was sprung under the Burg bastion, with such force that it shook half the city like an earthquake.  The bastion was rent and shattered for a width of more than thirty feet, portions of its walls being hurled far and wide.

Into the great breach made the assailants poured in an eager multitude.  But the defenders were equally alert, and drove them back with loss.  On the following day they charged again, and were again repulsed by the brave Viennese, the ruined bastion becoming a very gulf of death.