UFO's in paintings:

The Crucifixion,  Yugoslavian, 1350, 

Kosovo, Yugoslavia

"Madonna and Child with the Infant St John", which can be found in the Hercules Room of the Palazzo Vecchio and is affectionately known locally as "Madonna dell'UFO" or "Our Lady of the Flying Saucer". It was painted in the 15th century, and has been variously attributed to Domenico Ghirlandaio, Filippino Lippi, Sebastiano Mainardi and to Jacopo del Sellaio.

In 1538 AD a tapestry was created in the city of Bruges in Belgium, known as the Summer's Triumph.

Some historians have suggested that these objects represent the significance of this ruler coming to power and that he had the support of the 'divine'. 

Our Lady of Fatima as a UFO - Jacques Vallée