Maybe too ambitious for a one month jam but wow did you get far!
Core mechanics are all here and while it could still use some polish in a few places, the overall presentation is very impressive!
Giving names to all the little Knights and warriors was a great touch and the building descriptions are really fun!
It does have a bit of a laid back feeling to it, being as you never directly control or order anybody about. But I kind of liked that.
The only missing feature I'd say would be some kind of countdown to the next attack and maybe an indicator of how strong the attack will be.
I guess it's also a bit on the easy side. I never had enough gold to hire many soldiers, so I literally lost every battle until I finally happened upon a few gold mines and after that I won every battle!
Music was also very well chosen. Fit the setting, mood and tempo of the game perfectly.
Great work! And seriously impressive how much you got done in one month!