Freedom medals can be found in Swamps and Flatlands, usually in levels 5, 6, and 7. Also in lv 4 and 5 barb cities.
Justice medals are only obtained by attacking any NPC cities that are level 10.

The number of cities u can hold is based on ur title.. (i.e. Civilian, Knight, Baronet, Baron, Viscount, Earl, Marquis, Duke, Furstin, Prinzessin) After each promotion in title, you can build another city, all the way up to a total of ten cities. (Civilian being 1 city and Prinzessin being 10 cities)
Hope this helps!