Near the end of his leadership, Joshua reflects on his life's mission of dividing the land among the tribes of Israel. He makes it clear that the assignment of the territories is fully complete, even if the physical conquest of the land is still an ongoing process. By casting lots, Joshua fulfilled his primary duty, establishing the exact borders so that every tribe would know its designated portion [מלבי״ם]. This official division included not only the lands already captured but also the territories of the nations that remained unconquered [רש״י, מצודת דוד].
The geographic boundaries outline a clear distinction between what has been taken and what is yet to be captured. The territory spanning westward from the Jordan River primarily refers to the southeastern lands near the Jordan that Joshua successfully conquered during his lifetime [מלבי״ם]. The nations within this conquered region were fully accounted for in the distribution of the land [מצודת דוד, ביאור שטיינזלץ].
From the Jordan, the border stretches entirely across the land, reaching all the way to the Mediterranean Sea [רד״ק, מצודת דוד, ביאור שטיינזלץ]. This boundary marks the western direction, indicated by the setting of the sun [מצודת ציון]. This western region consists of the areas Joshua did not have time to conquer. However, despite being outside of current Israelite control, these lands have also been officially assigned by lot and divided among the tribes [מלבי״ם].