Do you think the strength of a kingdom is determined SOLELY by the strength of his army, or there are other factors?

Access to resources of all kinds and adequate leadership.

You should do some reading on the concept of “Soft Power” article

The leaders that make use of soft power are more effective,but it takes more work and has certain nuances and subtleties that hard power does not.

So @luigirovatti – the answer is NO, army strength is not / should not be the only measure of strength. Intelligent use of power is.

The short answer is that it depends largely on the circumstances.

I think the true strength lies in the resolve of the people.

Economy.

Strength of a kingdom isn’t solely dependent on its army but the survival of an evil king is as long as the army follows him.

Of course not.
Other vital factors are:
– economy to sustain the army economically
– agriculture to sustain the army nutritionally
– population to replenish losses the army sustains during war
– martial schools to train the replenishments
– manufacturing to equip the army
– infrastructure to quickly resupply and redeploy forces
– intelligence services to perform reliable recon, infiltration and sabotage of enemy forces, assassination of enemy leadership
– competent leadership to utilise their forces effectively
– ability to sustain their army’s morale
– difficult, rough homeland terrain and the ability to use it to impede invading forces
– access to powerful magic users
– a good number of big, fire-breathing dragons, preferrably not named “drogon”. seriously, a dragon named drogon? how lazy can you be in coming up with a name for your dragon?

That is equivalent to declaring the quality of a house dependent on the price of the hammers utilized in it’s erection.

Clearly not, not even in a simplistic board game only about military conquest, such as Risk.

Also you didn’t really define what you mean by “strength”.

Think of a person. Does their strength lie solely in their physical strength or does strength also depend on his or her character, wisdom and knowledge. If they have only physical strength they won’t be much respected. It is similar with countries.