what is its influence on other breeds?
Stallions were crossed with local mares adding Spanish bloodlines wherever they went, especially to other European breeds.
Andalusian horse
Spain's worldwide military activities between the 14th and 17th centuries called for large numbers of horses, more than could be supplied by native Spanish mares. Spanish custom also called for mounted troops to ride stallions, never mares or geldings. Due to these factors, Spanish stallions were crossed with local mares in many countries, adding Spanish bloodlines wherever they went, especially to other European breeds.

Because of the influence of the later Habsburg families, who ruled in both Spain and other nations of Europe, the Andalusian was crossbred with horses of Central Europe and the Low Countries and thus was closely related to many breeds that developed, including the Neapolitan horse, Groningen, Lipizzaner and Kladruber. 
what is andalusian horse? A horse breed what are some characteristics of this horse? Stallions and geldings average at the withers and in weight; mares average
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Andalusian horse [SEP] Influence on other breeds
Spain's worldwide military activities between the 14th and 17th centuries called for large numbers of horses, more than could be supplied by native Spanish mares. Spanish custom also called for mounted troops to ride stallions, never mares or geldings. Due to these factors, Spanish stallions were crossed with local mares in many countries, adding Spanish bloodlines wherever they went, especially to other European breeds. Because of the influence of the later Habsburg families, who ruled in both Spain and other nations of Europe, the Andalusian was crossbred with horses of Central Europe and the Low Countries and thus was closely related to many breeds that developed, including the Neapolitan horse, Groningen, Lipizzaner and Kladruber.