On Sunday, Venezuela plans to hold an election for governor and legislators to represent Essequibo — a sparsely populated, oil-rich territory.

But there’s one problem. Essequibo is internationally recognized as part of neighboring Guyana, not Venezuela.

Most countries and the 125,000 people who live in Essequibo all agree: It belongs to Guyana, a country of about 800,000, not Venezuela, a nation of roughly 28 million.

In staging legislative and regional elections on Sunday, including in Essequibo, Venezuela’s autocratic president, Nicolás Maduro, analysts say, is seeking to legitimize his rule abroad and also within his deeply dissatisfied nation, where the military’s loyalty is reportedly fraying.

Last year Mr. Maduro declared victory in a presidential election but did not provide any evidence to support his claim. Instead, tallies collected by election monitors showed that his opponent had won in a landslide. Many countries, including the United States, did not recognize Mr. Maduro as the winner.

Of particular concern to Venezuela’s government, according to analysts, were vote counts the opposition collected from military barracks showing that a large portion of the armed forces voted against Mr. Maduro.