How did the Assyrians rule their empire?

The Assyrian Empire placed royal family members and powerful military leaders as governors or lords of the foreign conquered kingdoms such as Egypt (modern day Egypt), Judah (modern day Israelite (Israel and Palestine)), Kizzuwatna (near the Gulf of İskenderun in modern day Turkey), Syria (modern day Syria), Urartu (modern-day Armenia), Cilicia (modern day Çukurova), Zamora (modern day Sulaimania Governate of Iraq), Elam (modern day Southwest Iran), Bazu orBamileke (modern day Cameroon), Kush (modern day Sudan), Mittani (modern day Northern Syria), Media (modern day Northwestern portions of Iran) Babylon (modern day Southern Iraq), Phoenicia (modern day Lebanon), Philistia (modern day coastal region that stretches roughly from Gaza in the South to Ashdod in the North of Israelite), Samaria (modern day correspondence to the North of the West Bank (Israel time)), Mannea (a territory in modern day Iran), and Persia (the rest of modern day Iran).