a 500+ page paper and parchment manuscript produced between 1495 and 1515. It details the arsenal and artillery innovations of the Habsburg monarch, Kaiser Maximilian I, who was something of an enthusiastic scholar and patron to a wide range of intellectual as well as military pursuits. He is credited with the development of the portable cannon and the establishment of the respected mercenary pikemen regiments . . . known as Landsknechts.
Kaiser, like the Russian term czar, is a corruption of the Latin caesar. The pronunciation changed when the term passed into the Teutonic languages (the OED claims it was the first Latin word to do so).
Although the German word Kaiser is indeed different from the original Latin Caesar, it's not much different. In classical Latin, the Cae would indeed have been pronounced Kai as in kind. It probably came into the Teutonic languages via Greek . It was originally the family name of Julius Caesar, meaning"hairy." There is a distinct possibility that this was intended humorously, since the Caesar men had a tendency to baldness. (Rather like calling a bald guy "Curly.")