All the Israelites from Dan to Beer-sheba and from the land of Gilead came out, and the community assembled as one body before the Lord at Mizpah.
References for Judges 20:1
The leaders of all the people and of all the tribes of Israel presented themselves in the assembly of God's people: 400,000 armed foot soldiers.
The Benjaminites heard that the Israelites had gone up to Mizpah. The Israelites asked, "Tell us, how did this outrage occur?"
The Levite, the husband of the murdered woman, answered: "I went to Gibeah in Benjamin with my concubine to spend the night.
Citizens of Gibeah ganged up on me and surrounded the house at night. They intended to kill me, but they raped my concubine, and she died.
Then I took my concubine and cut her in pieces, and sent her throughout Israel's territory, because they committed a horrible shame in Israel.