Nation:

“An Independent body politic; a society of men united together for the purpose of promoting their mutual safety and advantage by the joint efforts of their combined strength. But every combination of men who govern themselves independently of all others will not be considered a nation. A body of pirates, for example, who govern themselves, are not a nation. To constitute a nation, another ingredient is required. The body thus formed must respect other nations in general, and each of their members in particular. Such a society has her affairs and her interests; she deliberates and takes resolutions in common, thus becoming a moral person, who possesses an understanding and will peculiar to herself, and is susceptible of obligations and rights.” Vattel, Prelim. Ill, 2; 5 Pet. (U. S.) 52. See 1 Idaho (N. S.) 612.

 

Peace:

The tranquility enjoyed by a political society, internally by the good order which reigns among its members, and externally by the good understanding it has with all other nations. Applied to the internal regulations of a nation, peace imports, in a technical sense, not merely a state of repose and security as opposed to one of violence or warfare, but likewise a state of public order and decorum. - Black's Law 4th Edition

 

Ambassador:

In international law, a public officer, clothed with high diplomatic powers, commissioned by a sovereign prince or state to transact the international business of his government at the court of the country to which he is sent. -Black's Law 4th Edition