Joshua 15:1–63 can be divided into three parts:
The boundary allotment for Judah (Joshua 15:1–12)
The exploits of Caleb and his family (Joshua 15:13–19)
The cities and towns which belong to Judah (Joshua 15:20–63)
Though discussion of Judah’s inheritance began in Joshua 14:6, Joshua 15:1–63 provides the actual allotment for this tribe. Judah is given the largest inheritance in the land west of the Jordan (the land of Canaan proper). Most likely this is due to the fact that Judah had emerged as the most important tribe in Israel, Judah having received a special blessing from his father, Jacob (Genesis 49:8–12).1 The priority of Judah is also seen elsewhere in Scripture, for example Judges 1:1–2, where the Lord appoints Judah to go up first against the remaining Canaanites.
1 The allotment for the tribe of the people of Judah according to their clans reached southward to the boundary of Edom, to the wilderness of Zin at the farthest south.