you can have a higher population than 90. to get a higher population than 90 you have to finish the collections. Each collection is worth another 5 villagers, and I believe finishing all the collections is another 10 villagers. So in theory, 5x4 + 10 should be 30 more villagers. 90+30=120. However, for some reason, my villages with all the collections done only let me hold 115 villagers. i'm not sure if that is just me or if others are also stuck at 115. i know there are events that can push you over 115 also.

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