Just finished Turn 332 as the Spanish Medieval era. Completed Hospital les Invalides prior turn. Invading an independent peoples city. 5/5 city cap. Turn does not complete. Huge map, Endless length, 16:10 map layout, 8 competitors, one is already eliminated. Hit end turn and it just pends...

Reload the last save (turn 331), I can prevent it from occurring for up to 3 turns, but it always triggers. Unknown cause.