Solomon's reign was defined by massive territorial expansion and a royal majesty that demanded an exceptionally wealthy court and a vast royal table, fitting for a ruler of his supreme status [מלבי״ם]. His dominion operated on two distinct levels. On a global scale, his immense wisdom and glory earned him prestige, influence, and authority over all the kingdoms of the world. At the same time, his direct and practical rule was firmly established within specific geographic boundaries [חומת אנך].
These borders spanned a vast region, beginning at the great river. The primary approach among commentators is that this refers to the Euphrates River [רד״ק, ביאור שטיינזלץ], while another perspective suggests it refers to the river flowing out of Eden, marking the extreme eastern edge of his empire [מצודת דוד]. From that eastern boundary, the kingdom extended westward to the land of the Philistines and reached all the way south to the border of Egypt [ביאור שטיינזלץ].
The nations living within these territories lived in fear of Solomon [רד״ק]. While not every individual was directly enslaved, the entire region was subject to his authority. The surrounding peoples recognized him as the supreme monarch [ביאור שטיינזלץ], actively serving him and regularly bringing tribute and taxes [מצודת דוד].
This broad political control carried enormous economic benefits. Because the subject nations bore the heavy burden of taxes and tribute, the massive costs required to maintain the king's court and royal administration did not fall upon the Israelites. Instead, the people of Israel were able to live comfortably, enjoying the immense wealth and prosperity that flowed in from the surrounding lands [מלבי״ם].