Drugeth nodded. Like many Hungarian noblemen he was an experienced soldier. The Ottomans would have to mobilize a huge army to attack Vienna—and get that army and its equally enormous supply train through the Balkans. It was impossible to do so in winter, of course. But it was also essential that such an army not be left stranded in the middle of winter. There would be no way to keep it supplied with enough food, if it failed to seize Vienna.
The end result of these harsh logistical realities was that any attack launched by the Turks against Austria had to follow a rather fixed and rigid timetable. The invasion couldn't possibly be launched until the fresh spring grass arrived, or there wouldn't be enough grazing for the horses and oxen. There was no possibility of hauling enough fodder. Not with the immense number of livestock involved in such a campaign.
Traditionally, the Turks began their campaigning season at or near the time of the festival in honor of Hizir Hyas, the Moslem saint who protected travelers and other people in peril. That came in early May, by the Christian calendar.
Of course, the Turks wouldn't wait that long before they began moving their troops. They'd march them north to Belgrade in March and April, and launch the attack from there once the weather and grazing conditions permitted. Belgrade was roughly half the distance from Istanbul to Vienna, but the terrain over that final stretch was much more difficult for an army. Much of the terrain south of the Danube consisted of marshes and swamps.
The Turkish army was extremely well organized, true. Being honest, he acknowledged that it was better organized than the Austrian—or, indeed, most Christian armies. But it still couldn't move faster than ten or twelve miles a day. The earliest the Ottomans could reach Vienna would be late June or, more likely, sometime in July.
They couldn't afford to arrive much later than that, because once they did arrive they'd only have a few months to succeed in taking the city. If they hadn't done so by late autumn, they'd have no choice but to retreat back to Belgrade. Trying to keep an army of that size in fieldworks through winter would be almost certain disaster. Disease, exposure and hunger would slaughter far more of the sultan's soldiers than his enemy could. Such a disaster had overtaken the Ottoman army in 1529, when Suleiman the Magnificent delayed for too long before ordering a retreat, in hopes that a final assault would take Vienna.
So, Ferdinand was right. It was already June, and thus too late this year for a Turkish invasion.
"All right," said the emperor, a bit grumpily. "I'll agree to hold off any decision until the winter." He raised a rigid forefinger. "But! The price is that you have to undertake an inspection of the frontier fortifications. To see if the Turks really are planning any mischief for next year."
"Again? I inspected those forts less than—"
"Yes, again!" Ferdinand grimaced. There was some sympathy in the expression—not much—along with surly satisfaction at making Janos pay for impeding the royal will. "You can send your letters to the American woman just as well from horseback as from the comfort of your estates in Hungary."
Estates which, in point of fact, Janos hadn't seen in quite a while. That was because he'd been here in Vienna, serving the emperor in the capacity that the up-timers called "right-hand man."
But there was no point arguing the matter. Truth be told, Drugeth wouldn't mind doing such an inspection tour again. It was possible that the Ottomans had decided to attack Austria.
Murad was neither stupid nor weak-minded. He could study the up-time texts as well as anyone. Grantville's records with respect to Turkey were assumed to be even scantier than those relating to Austria. But Janos had his own spies in Grantville and he knew that was only true of the public records. There was one large private library in the town which, as it turned out, had a copy of a book by a man named Lord Kinross. The Ottoman Centuries, was its title. Janos had a copy of it himself, in his chambers in this very palace.
Assuming that Murad had gotten his hands on a copy also—and it would be foolish to assume otherwise—he was quite capable of drawing some lessons from the history recounted therein. The section dealing with Murad's own reign was quite extensive. If Drugeth were the sultan, there was one simple lesson he'd most likely draw from the Kinross book. In the end, the great Turkish power would be brought down not by Persians, the current enemy of the Ottomans, but by the armies of Christian nations.
So, Janos made no further demurral. He finished his glass of wine, rose, and gave his friend and emperor a little bow. "As you command, Your Majesty."
The ruler of the Austrian empire and head of the elder branch of the great Habsburg dynasty looked up at Drugeth. Once again, from under lowered brows.