Just tested this (whilst eating breakfast), made all settings lopsided in my favor. Settler difficulty (yawn), quick speed, Huge map, deleted all but one opposing Civ, and we're off.
Played Japan (irrelevant) and sent out my warrior, whilst simultaneously beginning the Scout spam plan I had devised. Warrior finds a Goody Hut, and guess what it is? Reveals three (3) Encampments. Nice.
First Social Policy is to open the Honor tree. (Duh.)
Send the Warrior and every Scout threrafter to swarm the closest Encampment, and here are the results:
T15 = First barb spawn (had four sides covered, it appeared in one of the two uncovered hexes. Killed.
T17 = First (and only) "Encampment Counterattack" on one of my fortified Scouts. Encamped barb left with one HP.
T20 = Full envelopment.
T26 = Golden Age (irrelevant).
T30 = Nothing. (As first spawn was T15, figured 15 x 2.)
T45 = Nothing. (15 x 3.)
T50 = Went to T50 just to be extra-sure; by my estimation, Encampment would have fielded three (3) new Warriors, including that first (and only) one, but nothing.
Conclusion: Surrounding an Encampment makes barb spawns impossible. Total waste of time and build time, obv., but my curiosity is at least sated. Useless information for all!
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