It is one of the proverbs learned as a child because it very graphically teaches them what can found in life. If you fall asleep or get confused, it may happen that when you return someone has taken your place. It has many popular deviations – quién fue a Morón, perdió su sillón [he who went to Morón, lost his armchair] – and it is actually poorly constructed as it should read “quien se fue de Sevilla, perdió su silla” [he who left Seville, lost his chair]. The saying is based on a historical fact. During the reign of Henry IV, between 1454 and 1474, the archbishopric of Santiago de Compostela was granted to a nephew of Alonso de Fonseca, who at that time was the Archbishop of Seville.
In those years the Galician city was experiencing a revolt and the nephew asked his uncle a favor that he bought peace to the city and they would temporarily exchange posts. When the uncle returned he found that his nephew had settled in the archbishopric of Seville and refused to return the post to his uncle. The nephew must have liked the heat of the south and the fried fish more than the Galician empanada and the rain of the north. Finally the uncle had to resort to a papal injunction and ask the King to intervene so that he could recover his seat.