This isn't easily accessible, you have to remember it yourself.
Theoratically it would be possible to have 1 territ. and conquer 150 territ's on "Conquerman" in 1 round but I doubt anyone has done that! (with escalating spoils of course but that's a condition for any sort of record breaking in this genre)
At the most I have managed to conquer 109 territ's on "Supermax: Prison Riot" in 1 round Game 5118140 !
Since I have never seen anyone conquer more than that in 1 round we'll have to call that a record untill someone can prove that they have conquered more territ's in 1 round !
Anyone who want's to post their record is very welcome! And so is all other response on this matter !
RedBaron0 has the current record with 121 territories conquered in 1 round!
This thread was created at the Strategy forum, viewtopic.php?f=58&t=91554&start=0 but I moved it here because it's the right forum for this topic!