Here is a passage on Nobunaga's attack on Mt. Hiei in 1571 by the Jesuit Luis Frois. From Michael Cooper's, They Came to Japan (pp. 98-99)
The Destruction of Hieizan
Knowing that he had them all on the top of the mountain, Nobunaga immediately gave the orders to set fire to Sakamoto and to put to the sword all those found within town. This was on September 29th ofthis year 1571, the Feast of the Dedication of the glorious St. Michael. And in order to show the bonzes who were up the mountain the little regard he paid to the chimeras (which they had described to him) of the punishments of Sanno, the second thing that he did was to burn all the temples of this idol which were below the foot of the mountain; he also destroyed by fire the seven universities so that nothing at all was left of them. Then deploying his army of 30,000 men in the form of a ring around the mountain, he gave the order to advance to the top. The bonzes began to resist with their weapons and wounded about 150 soldiers. But they were unable to withstand such a furious assault and were all put to the sword, together with the men, women, and children of Sakamoto, which is near the foot the mountain.
The next day, the last in september and the Feast of the glorious St. Jerome, they burnt down the large temple of Sanno, which, as i said was on the top of the mountain. Then Nobunaga ordered a large number of musketeers to go out into the hills and woods as if on a hunt; should they find any bonzes hiding there, they were not to spare the life of a single one of them. And this they duly did. But Nobunaga was not satisfied with this victory and desired to slake his thirst for vengeance even more and to increase his fame. So he commanded his whole army to go and plunder the remaining houses of the bonzes and to burn down all the four hundred odd temples of those famous universities of Hieizan. And on that same day all of them were destroyed, burnt down and reduced to ashes. Then he ordered the army to the town of Katata, which was unable to offer resistance and was also laid waste by fire. They told me that there had perished about 1,500 bonzes and the same number of layfolk, men, women and children."
Tenka no tame!