Discovered by who or what? If any organism can "discover" the "first country", then it could be any prokaryotic cell from the beginning of earth. There weren't "countries" then, although maybe we could say Pangaea. If you mean humans however, then we could point to the most widely accepted model of recent African origin of modern humans (or more commonly Out-of-Africa model), in which archaic Homo sapiens evolved out of Africa. Albeit Africa is not a country, it is the first area humans occupied.
Egypt was not the first country on the earth Iraq was the first country
The first country was U.S.A.
The first recognized sovereign nation was San Marino.
Greece, was the first country were containment was implemented
England was the first country
"Country First" "Country First"
first country to make a constitution
the first country to have glasses was italy
NoEthiopia was the first country in the world.
which is the first country developed hydroelectricity
Austria was the first country to be annexed.
the country !!