You might recognize the style from Alexia Sinclair's sister series, The Regal Twelve. This one features twelve nobles and monarchs.To create these amazing works, Alexia weaved together very specific elements from her own photos and illustrations. Here is how the series is described on her site:
'Legends of the lives of the nobles continue to captivate us today, from the pampered decadence of Louis XIV to the epic legend of Alexander the Great. Other rulers who also form this series are less renowned yet equally intriguing. An unusual blend of Royalty, their selection was based on their contrasts in leadership, their flamboyancies and their enduring influence upon society.'
via [Who Designed It?]