It didn't.
Spain is a parliamentary democracy.
Spain
It depends on what you mean by "democratic". There would be at the very least three dates for such "democratization":1824 when Mexico switched from a monarchy into a republic1917 when the ideals of the Mexican Revolution were written in the Mexican Constitution.2000 when the Partido Revolucionario Institucional(Institutional Revolutionary Party) ended it uncontested reign over Mexico's politics.
Presidential
Today, Spain is a constitutional/parliamentary democracy, so, yes, it is a democracy. It's previous government under Franco was a fascist dictatorship.
Spanish conquistadors found Mexico in 1519.
Spain is in Europe, Mexico is in North America.
Democracy
Spain’s royals were responsible for guiding in democracy.
It was first founded as Mexico-Tenochtitlan in 1325 by the Aztec people. In 1521 it became Mexico City, capital of the New Spain colony.
Mexico
Mexico was a colony of Spain from 1521 until 1821.