The United States of America

The United States of America is a country in North America. It is the primary setting for all of The Walking Dead, and Season One and the first part of Season Two of Fear the Walking Dead. It is bordered to the north by Canada and to the south by Mexico.

Pre-Apocalypse
Considered to be the only world superpower left after the end of the Cold War, the United States was an economic powerhouse and a world leader in technology and entertainment, among many other areas.

Post-Apocalypse
From information gleaned from the show, the United States appears to have been the origin for the (eventually global) outbreak, with no reports in any other country before the initial outbreak in the U.S.

It appears that the outbreak in the U.S. began west of the continental divide and spread eastwards across the continental United States, as well as northwards into Canada and southwards into Mexico.

The initial responders to the crises were local law enforcement agencies such as the California Highway Patrol and the Los Angeles Police Department and field offices of the Center for Disease Control followed by deployment of National Guard Units. However, lack of information about the infection itself and those it affected led to these organizations gradually being overrun.

The leadership of the U.S. Military (and it is assumed, high ranking members of the Federal Government) devised Operation Cobalt in order to try and control the outbreaks. First was the establishment of "Safe Zones" within major population centers with a view to use them as springboards to reclaim infected territory. The establishment of safe zones was followed by quarantine of suspected infected individuals (and their termination if infected, with their bodies being burned). If these measures were to fail, then the final step was the large scale bombing of major urban areas to kill the infected. The bombing of Los Angeles, California was seen in the first episode of Season 2 of FtWD. The bombing of other areas was confirmed by George Geary (Fear The Walking Dead) or witnessed by other survivors (such as Shane and Lorie witnessing Atlanta being bombed).

By the beginning of Season 2 of Fear, it is unknown how many states have been infected, with some reports at this point claiming eleven states having declared emergencies.

According to the last broadcast from the Park Ranger at Shuteye Peak, the bombing of major cities has had major ecological consequences. By his estimation, the fires caused by the bombing will wipe out Yosemite and the Searra Nevada within a week. (Fear the Walking Dead Radio Waves podcast).

In the North, it can be seen that there are still individuals guarding the U.S. boarder with Mexico. Whether they are sanctioned by the government, ordinary citizens concerned about 'immigration' or bandits is unknown.

By the time Rick Grimes awakes from his coma, all of mainland America has being overrun by the walker epidemic.