(CNN) Qasem Soleimani, who was killed by a US airstrike ordered by President Donald Trump at Baghdad International Airport on Friday, was hailed as a hero in Iran -- brave, charismatic and beloved by the troops.

Iran's supreme leader, Ayatollah Ali Khamenei, once called him a "living martyr of the revolution." But the United States viewed Iran's top general as a ruthless killer.

One of Iran's most powerful men, Soleimani cut a highly controversial figure. He was head of the Revolutionary Guards' Quds Force, an elite unit that handles Iran's overseas operations -- and one deemed to be a foreign terrorist organization by the US.

Having started his front line military career in the Iran-Iraq war during the early 1980s, Soleimani rose to prominence to become an indispensable figure in Iran, playing an instrumental role in spreading its influence in the Middle East.

JUST WATCHED Who are the Islamic Revolutionary Guard Corps? Replay More Videos ... MUST WATCH Who are the Islamic Revolutionary Guard Corps? 02:09

"He's been in combat his entire life. His soldiers love him. He's a quiet, charismatic guy, a strategic genius and a tactical operator," Lieutenant General Mark Hertling, a national security, intelligence and terrorism analyst, told CNN.

Read More