Yes. You will have to provide a police clearance for every country in which you have served for more than 12 months. This includes where you have been stationed at a military base in a foreign country.
If you are a current member of a military force, and have spent more than 12 months serving in a country other than your country of citizenship, you will also need to provide a letter from your military organisation attesting to your character. This is generally a letter from your commanding officer stating that you have not been convicted of any criminal offence during your time in the military.