From Web Gallery of Art: 

Spain's greatest painter was also one of the supreme artists of all time. A master of technique, highly individual in style, Diego Velázquez may have had a greater influence on European art than any other painter.  

Velázquez lived in Madrid as court painter. His paintings include landscapes, mythological and religious  subjects, and scenes from common life, called genre pictures. Most of them, however, are portraits of  court notables that rank with the portraits painted by Titian and Anthony Van Dyck.  

Duties of Velázquez' royal offices also occupied his time. He was eventually made marshal of the royal  household, and as such he was responsible for the royal quarters and for planning ceremonies.  

Velázquez was called the "noblest and most commanding man among the artists of his country." He was a master realist, and no painter has surpassed him in the ability to seize essential features and fix them on canvas with a few broad, sure strokes. "His men and women seem to breathe," it has been said; "his horses are full of action and his dogs of life."  

As court painter to Philip IV, Velázquez spent a large part of his life recording, in his cool, detached way, the objective appearance of this rigidly conventional royal household, with little  interpretation but with the keenest eye for selecting what was important for pictoral expression and with a control of paint  to secure exactly the desired effect.  

In painting these royal portraits, whatever interpretation he made or whatever emotional reaction he experienced he kept to himself. Royalty, courtliness of the most rigid character was his task to portray, not individual personality.  
(Web Gallery of Art) 
 

Notes 

John Singer Sarsgent

King Philip IV
1879?

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