There seems to be some lack of understanding out there on city strength so here is a very short guide to it NORMAL CITY The Base city strength is the strength of the strongest melee unit minus 10. The additional 10 to make it full strength only occurs when the unit garrisons it. So The Germans have built horsemen (strength 36) but they are not in the capital The city gets +2 per district which can be reduced by pillaging the district (buildings do not count but must be done) You can see in the picture the shields say the city has a strength of 33 but in fact it has a strength of 40. This is because terrain and difficulty bonuses are not included so be careful and rememeber. Only the current capital has +3 for a palace guard Wall at +2 is only ancient... Medieval +4, Renaissence +6 CITY STATES From the same game we can see Vilnius does not get a difficulty bonus against me Vilnius has a district so gets +2 from it Vilnius is a capital so has a palace guard +3 Vilnius is on a hill +3 Vilnius gets +3 external influence because there are 3 envoys there (despite being mine) If they had Bastions that would also show as +6 (enhanced Defences) but they do not have this MODERN WALLS Finally here is a city I hacked a modern wall into just to make it clear what effects it does Note that while the city has 200 HP, it has no walls and so gets no + modifier. This is why building Renaissence walls still costs +3 maintenance... because it gives your city +6 strength that modern 'walls' do not... they are not really modern walls, just city HP.