Paleologu was born in Bucharest, into an ancient Romanian boyar family that claimed descent from the Palaiologoi, the last ruling dynasty of the Byzantine Empire.
After the Communists regime was established, he was under surveillance by the Securitate, and he lived hidden and under a false name in Câmpulung until 1956, when he began working as a researcher at the Romanian Academy in the Institute of Ancient Art History.
At the penal colony Salcia from Brăila Swamp labor camps he met Ion Dezideriu Sîrbu, Alexandru Zub, and Sergiu Al-George [ro].
He was a National Liberal senator for Vrancea (on Romanian Democratic Convention lists) following the 1996 election, and reelected for Bucharest during the 2000 suffrage (serving until 2004).
In the years after 1989 he admitted in a book of interviews with historian and novelist Stelian Tănase that during the communist period he eventually ended up collaborating with the Securitate and asked Romanians to forgive him.