The particular aircraft (a DC-6B, I believe) was originally operated by Aramco, where it was used for oil field crew changes...originally multi stops Dhahran - Houston and return, then, when jet scheduled service to Rome from the USA was available, one stop to Rome, and return to Dhahran.
Bought new from Douglas and went directly to Aramco, as I recall.
The name painted on the nose was Camel One.