Francisco Vasquez de Coronado is considered to be a European explorer because he was from Europe and because he explored parts of North America. This allows him to be considered as one of the European explorers.
Coronado (he should be called “Vasquez”) was born in Salamanca, Spain in 1510. This makes him a European. His father was an important man in the government.
Coronado came over to the New World in 1535. He was, at that point, close to the Viceroy of New Spain. This meant that he was well connected to people high up in the government. While in New Spain (now Mexico), Coronado heard tales about legendary rich cities in the northern part of that region. Beginning in 1540, he led an expedition in search of these cities. Of course, they did not exist. However, Coronado’s exploration did advance the European understanding of the geography of the continent. It also established trails that would help allow the Spanish to colonize what is now the US Southwest. Because he was born in Spain and explored this area of the New World, he can be seen as a European explorer.