For six hundred years, the warrior-monks of Enryakuji had made themselves the most inconvenient institution in Japan. They descended on Kyoto when their demands went unmet, sometimes setting fire to the city's outskirts to emphasize the point. They maintained armed men — the 僧兵 (sōhei), warrior monks who trained in both scripture and combat — as a standing private army. When Nobunaga's enemies among the Asakura and Azai clans needed a mountain refuge in central Japan with direct sightlines over the roads to Kyoto, they found one at Enryakuji.

Nobunaga had tried patience first. In 1569, the Imperial Court ordered him to restore temple lands he had taken. He refused. The temple refused his counter-terms. He sent warnings. They sent armed resistance. He sent more warnings. They harbored more of his enemies. By 1571, the tactical situation was simple: Enryakuji could observe every troop movement near Kyoto, shelter hostile forces, and serve as a command post for any coalition that wished to fight him. Worse, it had never been successfully attacked — which meant every warlord in Japan was watching to see if Nobunaga would be the next one to flinch.

He did not flinch.

On the night of September 28, 1571, Nobunaga moved 30,000 troops into position in three coordinated columns. The western approach, the southern foothills, the eastern slope above Sakamoto — each was sealed by a separate force. The operation was conducted in darkness and near-silence. No attack was launched that night. The soldiers simply took their positions and waited.

The genius of the 包囲 (hōi) — the encirclement — was that it preceded the fire by hours, ensuring that when the burning began at dawn, there would be nowhere to run. It was not a military tactic in the conventional sense. It was an act of total closure.

At the temple complex, the night unfolded in ordinary rhythms. Residents from Sakamoto, the town at the mountain's base, had seen something moving in the dark below and fled upward — not out, not toward the roads, but toward the temple complex at the summit. Enryakuji had always been the safe place. Its record of surviving confrontation with secular authority was so complete that it had become an institutional assumption: this was where people went when things went wrong below. They gathered at Nemoto Nakado, the great central hall, and waited for morning.

The institution had been founded in 788 by the monk 最澄 (Saichō) to protect Kyoto from evil spirits approaching from the northeast. It sat at the spiritual hinge point of the capital's geography, and for eight centuries it had wielded that position like a lever over the city's politics. The Emperor Go-Shirakawa's lament — that three things in Japan refused his command, the Kamo River floods, the fall of dice, and the monks of Enryakuji — had passed into the language as an observation about forces too elemental to control.

Nobunaga was 37. He had been born to a minor lord in Owari Province. He had no particular lineage that entitled him to reorder the world. What he had was an ability to look at an institution that everyone else treated as a fact of nature and ask whether it actually had to exist.

The answer he intended to give, surrounded in silence outside the temple walls, was no.

His men held their positions through the night. The torches were not yet lit. That would come in the morning, on September 29, when the killing began. September 28 was something more fundamental: it was the night the mountain ran out of exits.